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| Title: Loss-of-function mutations in the rice homeobox gene OSH15 affect the architecture of internodes resulting in dwarf plants .
| | Author: Sato Y Sentoku N Miura Y Hirochika H Kitano H Matsuoka M | | Journal: EMBO J Year: 1999 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub10022841 Accession (PMID): 10022841 | | Abstract: The rice homeobox gene OSH15 ( Oryza sativa homeobox ) is a member of the knotted1-type homeobox gene family .
We report here on the identification and characterization of a loss-of-function mutation in OSH15 from a library of retrotransposon-tagged lines of rice .
Based on the phenotype and map position , we have identified three independent deletion alleles of the locus among conventional morphological mutants .
All of these recessive mutations , which are considered to be null alleles , exhibit defects in internode elongation .
Introduction of a 14 kbp genomic DNA fragment that includes all exons , introns and 5- and 3- flanking sequences of OSH15 complemented the defects in internode elongation , confirming that they were caused by the loss-of-function of OSH15 .
Internodes of the mutants had abnormal-shaped epidermal and hypodermal cells and showed an unusual arrangement of small vascular bundles .
These mutations demonstrate a role for OSH15 in the development of rice internodes .
This is the first evidence that the knotted1-type homeobox genes have roles other than shoot apical meristem formation and/or maintenance in plant development . | Matching Sentences:
[ Sen. 5, subscore: 2.00 ]: The rice homeobox gene OSH15 ( Oryza sativa homeobox ) is a member of the knotted1-type homeobox gene family . We report here on the identification and characterization of a loss-of-function mutation in OSH15 from a library of retrotransposon-tagged lines of rice . Based on the phenotype and map position , we have identified three independent deletion alleles of the locus among conventional morphological mutants . All of these recessive mutations , which are considered to be null alleles , exhibit defects in internode elongation . Introduction of a 14 kbp genomic DNA fragment that includes all exons , introns and 5- and 3- flanking sequences of OSH15 complemented the defects in internode elongation , confirming that they were caused by the loss-of-function of OSH15 . Internodes of the mutants had abnormal-shaped epidermal and hypodermal cells and showed an unusual arrangement of small vascular bundles . These mutations demonstrate a role for OSH15 in the development of rice internodes . This is the first evidence that the knotted1-type homeobox genes have roles other than shoot apical meristem formation and/or maintenance in plant development .
[ Sen. 1, subscore: 1.00 ]: The rice homeobox gene OSH15 ( Oryza sativa homeobox ) is a member of the knotted1-type homeobox gene family . We report here on the identification and characterization of a loss-of-function mutation in OSH15 from a library of retrotransposon-tagged lines of rice . Based on the phenotype and map position , we have identified three independent deletion alleles of the locus among conventional morphological mutants . All of these recessive mutations , which are considered to be null alleles , exhibit defects in internode elongation . Introduction of a 14 kbp genomic DNA fragment that includes all exons , introns and 5- and 3- flanking sequences of OSH15 complemented the defects in internode elongation , confirming that they were caused by the loss-of-function of OSH15 . Internodes of the mutants had abnormal-shaped epidermal and hypodermal cells and showed an unusual arrangement of small vascular bundles . These mutations demonstrate a role for OSH15 in the development of rice internodes . This is the first evidence that the knotted1-type homeobox genes have roles other than shoot apical meristem formation and/or maintenance in plant development .
[ Sen. 2, subscore: 1.00 ]: The rice homeobox gene OSH15 ( Oryza sativa homeobox ) is a member of the knotted1-type homeobox gene family . We report here on the identification and characterization of a loss-of-function mutation in OSH15 from a library of retrotransposon-tagged lines of rice . Based on the phenotype and map position , we have identified three independent deletion alleles of the locus among conventional morphological mutants . All of these recessive mutations , which are considered to be null alleles , exhibit defects in internode elongation . Introduction of a 14 kbp genomic DNA fragment that includes all exons , introns and 5- and 3- flanking sequences of OSH15 complemented the defects in internode elongation , confirming that they were caused by the loss-of-function of OSH15 . Internodes of the mutants had abnormal-shaped epidermal and hypodermal cells and showed an unusual arrangement of small vascular bundles . These mutations demonstrate a role for OSH15 in the development of rice internodes . This is the first evidence that the knotted1-type homeobox genes have roles other than shoot apical meristem formation and/or maintenance in plant development .
[ Sen. 7, subscore: 1.00 ]: The rice homeobox gene OSH15 ( Oryza sativa homeobox ) is a member of the knotted1-type homeobox gene family . We report here on the identification and characterization of a loss-of-function mutation in OSH15 from a library of retrotransposon-tagged lines of rice . Based on the phenotype and map position , we have identified three independent deletion alleles of the locus among conventional morphological mutants . All of these recessive mutations , which are considered to be null alleles , exhibit defects in internode elongation . Introduction of a 14 kbp genomic DNA fragment that includes all exons , introns and 5- and 3- flanking sequences of OSH15 complemented the defects in internode elongation , confirming that they were caused by the loss-of-function of OSH15 . Internodes of the mutants had abnormal-shaped epidermal and hypodermal cells and showed an unusual arrangement of small vascular bundles . These mutations demonstrate a role for OSH15 in the development of rice internodes . This is the first evidence that the knotted1-type homeobox genes have roles other than shoot apical meristem formation and/or maintenance in plant development .
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Score: 3.00 |
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| Title: Characterization of the KNOX class homeobox genes Oskn2 and Oskn3 identified in a collection of cDNA libraries covering the early stages of rice embryogenesis .
| | Author: Postma-Haarsma AD Verwoert II Stronk OP Koster J Lamers GE Hoge JH Meijer AH .
| | Journal: Plant Mol . Biol . Year: 1999 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub10080693 Accession (PMID): 10080693 | | Abstract: For identification of genes involved in embryogenesis in the model cereal rice , we have constructed a collection of cDNA libraries of well-defined stages of embryo development before , during and after organ differentiation .
Here , we focus on the possible role of KNOX ( maize Knotted1-like ) class homeobox genes in regulation of rice embryogenesis .
Three types of KNOX clones were identified in libraries of early zygotic embryos .
Two of these , Oskn2 and Oskn3 , encode newly described KNOX genes , whereas the third ( Oskn1 ) corresponds to the previously described OSH1 gene .
In situ hybridizations showed that during the early stages of embryo development , all three KNOX genes are expressed in the region where the shoot apical meristem ( SAM ) is organizing , suggesting that these genes are involved in regulating SAM formation .
Whereas OSH1 was previously proposed to function also in SAM maintenance , Oskn3 may be involved in patterning organ positions , as its expression was found to mark the boundaries of different embryonic organs following SAM formation .
The expression pattern of Oskn2 suggested an additional role in scutellum and epiblast development .
Transgenic expression of Oskn2 and Oskn3 in tobacco further supported their involvement in cell fate determination , like previously reported for Knotted1 and OSH1 ectopic expression .
Whereas Oskn3 transformants showed the most pronounced phenotypic effects during vegetative development , Oskn2 transformants showed relatively mild alterations in the vegetative phase but a more severely affected flower morphology .
The observation that the KNOX genes produce similar though distinct phenotypic reponses in tobacco , indicates that their gene products act on overlapping but different sets of target genes , or that cell-type specific factors determine their precise action . | Matching Sentences:
[ Sen. 4, subscore: 1.00 ]: For identification of genes involved in embryogenesis in the model cereal rice , we have constructed a collection of cDNA libraries of well-defined stages of embryo development before , during and after organ differentiation . Here , we focus on the possible role of KNOX ( maize Knotted1-like ) class homeobox genes in regulation of rice embryogenesis . Three types of KNOX clones were identified in libraries of early zygotic embryos . Two of these , Oskn2 and Oskn3 , encode newly described KNOX genes , whereas the third ( Oskn1 ) corresponds to the previously described OSH1 gene . In situ hybridizations showed that during the early stages of embryo development , all three KNOX genes are expressed in the region where the shoot apical meristem ( SAM ) is organizing , suggesting that these genes are involved in regulating SAM formation . Whereas OSH1 was previously proposed to function also in SAM maintenance , Oskn3 may be involved in patterning organ positions , as its expression was found to mark the boundaries of different embryonic organs following SAM formation . The expression pattern of Oskn2 suggested an additional role in scutellum and epiblast development . Transgenic expression of Oskn2 and Oskn3 in tobacco further supported their involvement in cell fate determination , like previously reported for Knotted1 and OSH1 ectopic expression . Whereas Oskn3 transformants showed the most pronounced phenotypic effects during vegetative development , Oskn2 transformants showed relatively mild alterations in the vegetative phase but a more severely affected flower morphology . The observation that the KNOX genes produce similar though distinct phenotypic reponses in tobacco , indicates that their gene products act on overlapping but different sets of target genes , or that cell-type specific factors determine their precise action .
[ Sen. 6, subscore: 1.00 ]: For identification of genes involved in embryogenesis in the model cereal rice , we have constructed a collection of cDNA libraries of well-defined stages of embryo development before , during and after organ differentiation . Here , we focus on the possible role of KNOX ( maize Knotted1-like ) class homeobox genes in regulation of rice embryogenesis . Three types of KNOX clones were identified in libraries of early zygotic embryos . Two of these , Oskn2 and Oskn3 , encode newly described KNOX genes , whereas the third ( Oskn1 ) corresponds to the previously described OSH1 gene . In situ hybridizations showed that during the early stages of embryo development , all three KNOX genes are expressed in the region where the shoot apical meristem ( SAM ) is organizing , suggesting that these genes are involved in regulating SAM formation . Whereas OSH1 was previously proposed to function also in SAM maintenance , Oskn3 may be involved in patterning organ positions , as its expression was found to mark the boundaries of different embryonic organs following SAM formation . The expression pattern of Oskn2 suggested an additional role in scutellum and epiblast development . Transgenic expression of Oskn2 and Oskn3 in tobacco further supported their involvement in cell fate determination , like previously reported for Knotted1 and OSH1 ectopic expression . Whereas Oskn3 transformants showed the most pronounced phenotypic effects during vegetative development , Oskn2 transformants showed relatively mild alterations in the vegetative phase but a more severely affected flower morphology . The observation that the KNOX genes produce similar though distinct phenotypic reponses in tobacco , indicates that their gene products act on overlapping but different sets of target genes , or that cell-type specific factors determine their precise action .
[ Sen. 8, subscore: 1.00 ]: For identification of genes involved in embryogenesis in the model cereal rice , we have constructed a collection of cDNA libraries of well-defined stages of embryo development before , during and after organ differentiation . Here , we focus on the possible role of KNOX ( maize Knotted1-like ) class homeobox genes in regulation of rice embryogenesis . Three types of KNOX clones were identified in libraries of early zygotic embryos . Two of these , Oskn2 and Oskn3 , encode newly described KNOX genes , whereas the third ( Oskn1 ) corresponds to the previously described OSH1 gene . In situ hybridizations showed that during the early stages of embryo development , all three KNOX genes are expressed in the region where the shoot apical meristem ( SAM ) is organizing , suggesting that these genes are involved in regulating SAM formation . Whereas OSH1 was previously proposed to function also in SAM maintenance , Oskn3 may be involved in patterning organ positions , as its expression was found to mark the boundaries of different embryonic organs following SAM formation . The expression pattern of Oskn2 suggested an additional role in scutellum and epiblast development . Transgenic expression of Oskn2 and Oskn3 in tobacco further supported their involvement in cell fate determination , like previously reported for Knotted1 and OSH1 ectopic expression . Whereas Oskn3 transformants showed the most pronounced phenotypic effects during vegetative development , Oskn2 transformants showed relatively mild alterations in the vegetative phase but a more severely affected flower morphology . The observation that the KNOX genes produce similar though distinct phenotypic reponses in tobacco , indicates that their gene products act on overlapping but different sets of target genes , or that cell-type specific factors determine their precise action .
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Score: 5.00 |
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| Title: Initiation of shoot apical meristem in rice : characterization of four SHOOTLESS genes .
| | Author: Satoh N Hong SK Nishimura A Matsuoka M Kitano H Nagato Y | | Journal: Development Year: 1999 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub10409508 Accession (PMID): 10409508 | | Abstract: The regulatory mechanism of shoot apical meristem ( SAM ) initiation is an important subject in developmental plant biology .
We characterized nine recessive mutations derived from four independent loci ( SHL1-SHL4 ) causing the deletion of the SAM .
Radicles were produced in these mutant embryos .
Concomitant with the loss of SAM , two embryo-specific organs , coleoptile and epiblast , were lost , but the scutellum was formed normally .
Therefore , differentiation of radicle and scutellum is regulated independently of SAM , but that of coleoptile and epiblast may depend on SAM .
Regeneration experiments using adventitious shoots from the scutellum-derived calli showed that no adventitious shoots were regenerated in any shl mutant .
However , small adventitious leaves were observed in both mutant and wild-type calli , but they soon became necrotic and showed no extensive growth .
Thus , leaf primordia can initiate in the absence of SAM , but their extensive growth requires the SAM .
An in situ hybridization experiment using a rice homeobox gene , OSH1 , as a probe revealed that shl1 and shl2 modified the expression domain of OSH1 , but normal expression of OSH1 was observed in shl3 and shl4 embryos .
Accordingly , SHL1 and SHL2 function upstream of OSH1 , and SHL3 and SHL4 downstream or independently of OSH1 .
These shl mutants are useful for elucidating the genetic program driving SAM initiation and for unraveling the interrelationships among various organs in grass embryos . | Matching Sentences:
[ Sen. 9, subscore: 3.00 ]: The regulatory mechanism of shoot apical meristem ( SAM ) initiation is an important subject in developmental plant biology . We characterized nine recessive mutations derived from four independent loci ( SHL1-SHL4 ) causing the deletion of the SAM . Radicles were produced in these mutant embryos . Concomitant with the loss of SAM , two embryo-specific organs , coleoptile and epiblast , were lost , but the scutellum was formed normally . Therefore , differentiation of radicle and scutellum is regulated independently of SAM , but that of coleoptile and epiblast may depend on SAM . Regeneration experiments using adventitious shoots from the scutellum-derived calli showed that no adventitious shoots were regenerated in any shl mutant . However , small adventitious leaves were observed in both mutant and wild-type calli , but they soon became necrotic and showed no extensive growth . Thus , leaf primordia can initiate in the absence of SAM , but their extensive growth requires the SAM . An in situ hybridization experiment using a rice homeobox gene , OSH1 , as a probe revealed that shl1 and shl2 modified the expression domain of OSH1 , but normal expression of OSH1 was observed in shl3 and shl4 embryos . Accordingly , SHL1 and SHL2 function upstream of OSH1 , and SHL3 and SHL4 downstream or independently of OSH1 . These shl mutants are useful for elucidating the genetic program driving SAM initiation and for unraveling the interrelationships among various organs in grass embryos .
[ Sen. 10, subscore: 2.00 ]: The regulatory mechanism of shoot apical meristem ( SAM ) initiation is an important subject in developmental plant biology . We characterized nine recessive mutations derived from four independent loci ( SHL1-SHL4 ) causing the deletion of the SAM . Radicles were produced in these mutant embryos . Concomitant with the loss of SAM , two embryo-specific organs , coleoptile and epiblast , were lost , but the scutellum was formed normally . Therefore , differentiation of radicle and scutellum is regulated independently of SAM , but that of coleoptile and epiblast may depend on SAM . Regeneration experiments using adventitious shoots from the scutellum-derived calli showed that no adventitious shoots were regenerated in any shl mutant . However , small adventitious leaves were observed in both mutant and wild-type calli , but they soon became necrotic and showed no extensive growth . Thus , leaf primordia can initiate in the absence of SAM , but their extensive growth requires the SAM . An in situ hybridization experiment using a rice homeobox gene , OSH1 , as a probe revealed that shl1 and shl2 modified the expression domain of OSH1 , but normal expression of OSH1 was observed in shl3 and shl4 embryos . Accordingly , SHL1 and SHL2 function upstream of OSH1 , and SHL3 and SHL4 downstream or independently of OSH1 . These shl mutants are useful for elucidating the genetic program driving SAM initiation and for unraveling the interrelationships among various organs in grass embryos .
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Score: 1.00 |
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| Title: Shoot organization genes regulate shoot apical meristem organization and the pattern of leaf primordium initiation in rice .
| | Author: Itoh JI Kitano H Matsuoka M Nagato Y | | Journal: Plant Cell Year: 2000 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11090216 Accession (PMID): 11090216 | | Abstract: The mechanism regulating the pattern of leaf initiation was analyzed by using shoot organization ( sho ) mutants derived from three loci ( SHO1 , SHO2 , and SHO3 ) .
In the early vegetative phase , sho mutants show an increased rate of leaf production with random phyllotaxy .
The resulting leaves are malformed , threadlike , or short and narrow .
Their shoot apical meristems are relatively low and wide , that is , flat shaped , although their shape and size are highly variable among plants of the same genotype .
Statistical analysis reveals that the shape of the shoot meristem rather than its size is closely correlated with the variations of plastochron and phyllotaxy .
Rapid and random leaf production in sho mutants is correlated with the frequent and disorganized cell divisions in the shoot meristem and with a reduction of expression domain of a rice homeobox gene , OSH1 .
These changes in the organization and behavior of the shoot apical meristems suggest that sho mutants have fewer indeterminate cells and more determinate cells than wild type , with many cells acting as leaf founder cells .
Thus , the SHO genes have an important role in maintaining the proper organization of the shoot apical meristem , which is essential for the normal initiation pattern of leaf primordia . | Matching Sentences:
[ Sen. 6, subscore: 1.00 ]: The mechanism regulating the pattern of leaf initiation was analyzed by using shoot organization ( sho ) mutants derived from three loci ( SHO1 , SHO2 , and SHO3 ) . In the early vegetative phase , sho mutants show an increased rate of leaf production with random phyllotaxy . The resulting leaves are malformed , threadlike , or short and narrow . Their shoot apical meristems are relatively low and wide , that is , flat shaped , although their shape and size are highly variable among plants of the same genotype . Statistical analysis reveals that the shape of the shoot meristem rather than its size is closely correlated with the variations of plastochron and phyllotaxy . Rapid and random leaf production in sho mutants is correlated with the frequent and disorganized cell divisions in the shoot meristem and with a reduction of expression domain of a rice homeobox gene , OSH1 . These changes in the organization and behavior of the shoot apical meristems suggest that sho mutants have fewer indeterminate cells and more determinate cells than wild type , with many cells acting as leaf founder cells . Thus , the SHO genes have an important role in maintaining the proper organization of the shoot apical meristem , which is essential for the normal initiation pattern of leaf primordia .
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Score: 1.00 |
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| Title: The LAX1 and FRIZZY PANICLE 2 genes determine the inflorescence architecture of rice by controlling rachis-branch and spikelet development .
| | Author: Komatsu M Maekawa M Shimamoto K Kyozuka J | | Journal: Dev . Biol . Year: 2001 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11237465 Accession (PMID): 11237465 | | Abstract: We have analyzed two mutants that exhibit altered panicle architecture in rice ( Oryza sativa L ) .
In lax1-2 , which is a new and stronger allele of the previously reported lax mutant , initiation and/or maintenance of rachis-branches , lateral spikelets , and terminal spikelets was severely prevented .
In situ hybridization analysis using OSH1 , a rice knotted1 ( kn1 ) ortholog , confirmed the absence of lateral meristems in lax1-2 panicles .
These defects indicate that the LAX1 gene is required for the initiation/maintenance of axillary meristems in the rice panicle .
In addition to its role in forming lateral meristems , the wild-type LAX1 gene acts as a floral meristem identity gene which specifies the terminal spikelet meristem .
A comparison of the defects in lax1-1 and lax1-2 plants suggested that the sensitivities to reduced LAX1 activity were not uniform among different types of meristems .
In the fzp2 mutant panicle , the basic branching pattern of the panicle was indistinguishable from that of the wild type ; however , specification of both terminal and lateral spikelet meristems was blocked , and sequential rounds of branching occurred at the point where the spikelet meristems are initiated in the wild-type panicle .
This resulted in the generation of a panicle composed of excessive ramification of rachis-branches .
The lax1-1 fzp2 double mutants exhibited a novel , basically additive , phenotype , which suggests that LAX1 and FZP2 function in genetically independent pathways . | Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: We have analyzed two mutants that exhibit altered panicle architecture in rice ( Oryza sativa L ) . In lax1-2 , which is a new and stronger allele of the previously reported lax mutant , initiation and/or maintenance of rachis-branches , lateral spikelets , and terminal spikelets was severely prevented . In situ hybridization analysis using OSH1 , a rice knotted1 ( kn1 ) ortholog , confirmed the absence of lateral meristems in lax1-2 panicles . These defects indicate that the LAX1 gene is required for the initiation/maintenance of axillary meristems in the rice panicle . In addition to its role in forming lateral meristems , the wild-type LAX1 gene acts as a floral meristem identity gene which specifies the terminal spikelet meristem . A comparison of the defects in lax1-1 and lax1-2 plants suggested that the sensitivities to reduced LAX1 activity were not uniform among different types of meristems . In the fzp2 mutant panicle , the basic branching pattern of the panicle was indistinguishable from that of the wild type ; however , specification of both terminal and lateral spikelet meristems was blocked , and sequential rounds of branching occurred at the point where the spikelet meristems are initiated in the wild-type panicle . This resulted in the generation of a panicle composed of excessive ramification of rachis-branches . The lax1-1 fzp2 double mutants exhibited a novel , basically additive , phenotype , which suggests that LAX1 and FZP2 function in genetically independent pathways .
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Score: 4.00 |
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| Title: KNOX homeobox genes are sufficient in maintaining cultured cells in an undifferentiated state in rice .
| | Author: Ito Y Eiguchi M Kurata N | | Journal: Genesis Year: 2001 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11536429 Accession (PMID): 11536429 | | Abstract: We produced transgenic rice calli , which constitutively express each of four KNOX family class 1 homeobox genes of rice , OSH1 , OSH16 , OSH15 , and OSH71 , and found that constitutive and ectopic expression of such genes inhibits normal regeneration from transformed calli , which showed continuous growth around their shoot-regenerating stages .
Transgenic calli transferred onto regeneration medium began to display green spots , a sign of regeneration , but most of the transformants continued to propagate green spots at given stages .
In the normal shoot-regeneration process of calli , expression of endogenous OSH1 was restricted in presumptive shoot-regenerating regions of calli and not observed in other areas .
This restricted expression pattern should be required for further differentiation of the regenerating shoots .
Thus our present results support the proposed function that KNOX family class 1 homeobox genes play a role in the formation and maintenance of the undetermined meristematic state of cells . | Matching Sentences:
[ Sen. 1, subscore: 3.00 ]: We produced transgenic rice calli , which constitutively express each of four KNOX family class 1 homeobox genes of rice , OSH1 , OSH16 , OSH15 , and OSH71 , and found that constitutive and ectopic expression of such genes inhibits normal regeneration from transformed calli , which showed continuous growth around their shoot-regenerating stages . Transgenic calli transferred onto regeneration medium began to display green spots , a sign of regeneration , but most of the transformants continued to propagate green spots at given stages . In the normal shoot-regeneration process of calli , expression of endogenous OSH1 was restricted in presumptive shoot-regenerating regions of calli and not observed in other areas . This restricted expression pattern should be required for further differentiation of the regenerating shoots . Thus our present results support the proposed function that KNOX family class 1 homeobox genes play a role in the formation and maintenance of the undetermined meristematic state of cells .
[ Sen. 3, subscore: 1.00 ]: We produced transgenic rice calli , which constitutively express each of four KNOX family class 1 homeobox genes of rice , OSH1 , OSH16 , OSH15 , and OSH71 , and found that constitutive and ectopic expression of such genes inhibits normal regeneration from transformed calli , which showed continuous growth around their shoot-regenerating stages . Transgenic calli transferred onto regeneration medium began to display green spots , a sign of regeneration , but most of the transformants continued to propagate green spots at given stages . In the normal shoot-regeneration process of calli , expression of endogenous OSH1 was restricted in presumptive shoot-regenerating regions of calli and not observed in other areas . This restricted expression pattern should be required for further differentiation of the regenerating shoots . Thus our present results support the proposed function that KNOX family class 1 homeobox genes play a role in the formation and maintenance of the undetermined meristematic state of cells .
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Score: 3.00 |
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| Title: Functional analysis of the conserved domains of a rice KNOX homeodomain protein , OSH15 .
| | Author: Nagasaki H Sakamoto T Sato Y Matsuoka M | | Journal: Plant Cell Year: 2001 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11549765 Accession (PMID): 11549765 | | Abstract: The rice KNOX protein OSH15 consists of four conserved domains : the MEINOX domain , which can be divided into two subdomains ( KNOX1 and KNOX2 ) ; the GSE domain ; the ELK domain ; and the homeodomain ( HD ) .
To investigate the function of each domain , we generated 10 truncated proteins with deletions in the conserved domains and four proteins with mutations in the conserved amino acids in the HD .
Transgenic analysis suggested that KNOX2 and HD are essential for inducing the abnormal phenotype and that the KNOX1 and ELK domains affect phenotype severity .
We also found that both KNOX2 and HD are necessary for homodimerization and that only HD is needed for binding of OSH15 to its target sequence .
Transactivation studies suggested that both the KNOX1 and ELK domains play a role in suppressing target gene expression .
On the basis of these findings , we propose that overproduced OSH15 probably acts as a dimer and may ectopically suppress the expression of target genes that induce abnormal morphology in transgenic plants . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: The rice KNOX protein OSH15 consists of four conserved domains : the MEINOX domain , which can be divided into two subdomains ( KNOX1 and KNOX2 ) ; the GSE domain ; the ELK domain ; and the homeodomain ( HD ) . To investigate the function of each domain , we generated 10 truncated proteins with deletions in the conserved domains and four proteins with mutations in the conserved amino acids in the HD . Transgenic analysis suggested that KNOX2 and HD are essential for inducing the abnormal phenotype and that the KNOX1 and ELK domains affect phenotype severity . We also found that both KNOX2 and HD are necessary for homodimerization and that only HD is needed for binding of OSH15 to its target sequence . Transactivation studies suggested that both the KNOX1 and ELK domains play a role in suppressing target gene expression . On the basis of these findings , we propose that overproduced OSH15 probably acts as a dimer and may ectopically suppress the expression of target genes that induce abnormal morphology in transgenic plants .
[ Sen. 4, subscore: 1.00 ]: The rice KNOX protein OSH15 consists of four conserved domains : the MEINOX domain , which can be divided into two subdomains ( KNOX1 and KNOX2 ) ; the GSE domain ; the ELK domain ; and the homeodomain ( HD ) . To investigate the function of each domain , we generated 10 truncated proteins with deletions in the conserved domains and four proteins with mutations in the conserved amino acids in the HD . Transgenic analysis suggested that KNOX2 and HD are essential for inducing the abnormal phenotype and that the KNOX1 and ELK domains affect phenotype severity . We also found that both KNOX2 and HD are necessary for homodimerization and that only HD is needed for binding of OSH15 to its target sequence . Transactivation studies suggested that both the KNOX1 and ELK domains play a role in suppressing target gene expression . On the basis of these findings , we propose that overproduced OSH15 probably acts as a dimer and may ectopically suppress the expression of target genes that induce abnormal morphology in transgenic plants .
[ Sen. 6, subscore: 1.00 ]: The rice KNOX protein OSH15 consists of four conserved domains : the MEINOX domain , which can be divided into two subdomains ( KNOX1 and KNOX2 ) ; the GSE domain ; the ELK domain ; and the homeodomain ( HD ) . To investigate the function of each domain , we generated 10 truncated proteins with deletions in the conserved domains and four proteins with mutations in the conserved amino acids in the HD . Transgenic analysis suggested that KNOX2 and HD are essential for inducing the abnormal phenotype and that the KNOX1 and ELK domains affect phenotype severity . We also found that both KNOX2 and HD are necessary for homodimerization and that only HD is needed for binding of OSH15 to its target sequence . Transactivation studies suggested that both the KNOX1 and ELK domains play a role in suppressing target gene expression . On the basis of these findings , we propose that overproduced OSH15 probably acts as a dimer and may ectopically suppress the expression of target genes that induce abnormal morphology in transgenic plants .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
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| Title: The SHOOTLESS2 and SHOOTLESS1 genes are involved in both initiation and maintenance of the shoot apical meristem through regulating the number of indeterminate cells .
| | Author: Satoh N Itoh J Nagato Y | | Journal: Genetics Year: 2003 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub12750344 Accession (PMID): 12750344 | | Abstract: To characterize the SHL2 and SHL1 genes in detail , we analyzed three strains carrying weak alleles of SHL2 , shl2-6 , shl2-7 , and shl2-8 , and one weak allele of SHL1 , shl1-3 .
In contrast to strong alleles , which result in lack of shoot meristem , strains bearing these weak alleles formed shoot meristem frequently during embryogenesis .
In shl2-6 and shl2-7 mutants , the meristem was lost during seed development .
Only the shl2-8 mutant could survive after germination , but it showed abnormal initiation pattern and morphology of leaves .
In strains bearing the weak alleles , the shoot meristem was composed of a small number of indeterminate cells and ultimately converted into leaf primordium .
The shl1-3 mutant showed phenotypes similar to those of shl2-8 .
Thus SHL2 and SHL1 are required for both initiation and maintenance of shoot meristem .
In shl2 mutants , there was a positive correlation between the size of the expression domain of OSH1 representing the number of indeterminate cells , the frequency of shoot meristem initiation , and the duration of meristem survival Thus the shoot meristem will not initiate in an "all-or-nothing" fashion , but is formed in various degrees depending on the strength of the alleles .
Double-mutant analyses indicate that SHL2 functions upstream of SHO to establish proper organization of the shoot meristem . | Matching Sentences:
[ Sen. 8, subscore: 1.00 ]: To characterize the SHL2 and SHL1 genes in detail , we analyzed three strains carrying weak alleles of SHL2 , shl2-6 , shl2-7 , and shl2-8 , and one weak allele of SHL1 , shl1-3 . In contrast to strong alleles , which result in lack of shoot meristem , strains bearing these weak alleles formed shoot meristem frequently during embryogenesis . In shl2-6 and shl2-7 mutants , the meristem was lost during seed development . Only the shl2-8 mutant could survive after germination , but it showed abnormal initiation pattern and morphology of leaves . In strains bearing the weak alleles , the shoot meristem was composed of a small number of indeterminate cells and ultimately converted into leaf primordium . The shl1-3 mutant showed phenotypes similar to those of shl2-8 . Thus SHL2 and SHL1 are required for both initiation and maintenance of shoot meristem . In shl2 mutants , there was a positive correlation between the size of the expression domain of OSH1 representing the number of indeterminate cells , the frequency of shoot meristem initiation , and the duration of meristem survival Thus the shoot meristem will not initiate in an "all-or-nothing" fashion , but is formed in various degrees depending on the strength of the alleles . Double-mutant analyses indicate that SHL2 functions upstream of SHO to establish proper organization of the shoot meristem .
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Score: 2.00 |
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| Title: Rice globular embryo 4 ( gle4 ) mutant is defective in radial pattern formation during embryogenesis .
| | Author: Kamiya N Nishimura A Sentoku N Takabe E Nagato Y Kitano H Matsuoka M | | Journal: Plant Cell Physiol .
Year: 2003 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub14519768 Accession (PMID): 14519768 | | Abstract: In higher plants , the main elements of the fundamental body plan , the apical-basal and radial patterns , are established during embryogenesis .
We have isolated several globular embryo ( gle ) mutants of rice that fail to develop any embryonic organs .
We expected that these gle mutants might include mutants defective in their radial pattern formation ability .
We developed two markers specifically staining the L2 and L3 layers ( OsSCR and OsPNH1 , respectively ) and characterized the gle mutants by using these markers in addition to the already developed markers Roc1 ( marker for the L1 layer ) , Ramy1A ( marker of the L1 layer of the epithelium ) , and OSH1 ( marker of the apical region ) .
One of the gle mutants , gle4 , expressed Roc1 and Ramy1A at the normal positions , but other markers exhibited an abnormal expression pattern ; that is , both OsPNH1 and OsSCR were expressed in the central region of the embryo and OSH1 expression was not observed .
Calli from the gle4 epithelium regenerated plants with abnormal morphologies .
These results indicate that the GLE4 gene is involved in radial pattern formation during rice embryogenesis to differentiate the L2 and L3 layers , but is not involved in the establishment of the L1 layer or in the formation of embryonic organs . | Matching Sentences:
[ Sen. 4, subscore: 1.00 ]: In higher plants , the main elements of the fundamental body plan , the apical-basal and radial patterns , are established during embryogenesis . We have isolated several globular embryo ( gle ) mutants of rice that fail to develop any embryonic organs . We expected that these gle mutants might include mutants defective in their radial pattern formation ability . We developed two markers specifically staining the L2 and L3 layers ( OsSCR and OsPNH1 , respectively ) and characterized the gle mutants by using these markers in addition to the already developed markers Roc1 ( marker for the L1 layer ) , Ramy1A ( marker of the L1 layer of the epithelium ) , and OSH1 ( marker of the apical region ) . One of the gle mutants , gle4 , expressed Roc1 and Ramy1A at the normal positions , but other markers exhibited an abnormal expression pattern ; that is , both OsPNH1 and OsSCR were expressed in the central region of the embryo and OSH1 expression was not observed . Calli from the gle4 epithelium regenerated plants with abnormal morphologies . These results indicate that the GLE4 gene is involved in radial pattern formation during rice embryogenesis to differentiate the L2 and L3 layers , but is not involved in the establishment of the L1 layer or in the formation of embryonic organs .
[ Sen. 5, subscore: 1.00 ]: In higher plants , the main elements of the fundamental body plan , the apical-basal and radial patterns , are established during embryogenesis . We have isolated several globular embryo ( gle ) mutants of rice that fail to develop any embryonic organs . We expected that these gle mutants might include mutants defective in their radial pattern formation ability . We developed two markers specifically staining the L2 and L3 layers ( OsSCR and OsPNH1 , respectively ) and characterized the gle mutants by using these markers in addition to the already developed markers Roc1 ( marker for the L1 layer ) , Ramy1A ( marker of the L1 layer of the epithelium ) , and OSH1 ( marker of the apical region ) . One of the gle mutants , gle4 , expressed Roc1 and Ramy1A at the normal positions , but other markers exhibited an abnormal expression pattern ; that is , both OsPNH1 and OsSCR were expressed in the central region of the embryo and OSH1 expression was not observed . Calli from the gle4 epithelium regenerated plants with abnormal morphologies . These results indicate that the GLE4 gene is involved in radial pattern formation during rice embryogenesis to differentiate the L2 and L3 layers , but is not involved in the establishment of the L1 layer or in the formation of embryonic organs .
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Score: 1.00 |
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| Title: The gene FLORAL ORGAN NUMBER1 regulates floral meristem size in rice and encodes a leucine-rich repeat receptor kinase orthologous to Arabidopsis CLAVATA1 .
| | Author: Suzaki T Sato M Ashikari M Miyoshi M Nagato Y Hirano HY .
| | Journal: Development Year: 2004 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub15509765 Accession (PMID): 15509765 | | Abstract: The regulation of floral organ number is closely associated with floral meristem size .
Mutations in the gene FLORAL ORGAN NUMBER1 ( FON1 ) cause enlargement of the floral meristem in Oryza sativa ( rice ) , resulting in an increase in the number of all floral organs .
Ectopic floral organs develop in the whorl of each organ and/or in the additional whorls that form .
Inner floral organs are more severely affected than outer floral organs .
Many carpel primordia develop indeterminately , and undifferentiated meristematic it issues remain in the center in almost-mature flowers .
Consistent with this result , OSH1 , a molecular marker of meristematic indeterminate cells in rice , continues to be expressed in this region .
Although floral meristems are strongly affected by the fon1-2 mutation , vegetative and inflorescence meristems are largely normal , even in this strong allele .
We isolated the FON1 gene by positional cloning and found that it encodes a leucine-rich repeat receptor-like kinase most similar to CLAVATA1 ( CLV1 ) in Arabidopsis thaliana .
This suggests that a pathway similar to the CLV signaling system that regulates meristem maintenance in Arabidopsis is conserved in the grass family .
Unlike CLV1 , which is predominantly expressed in the L3 layer of the shoot meristem , FON1 is expressed throughout the whole floral meristem , suggesting that small modifications to the CLV signaling pathway may be required to maintain the floral meristem in rice .
In addition , FON1 transcripts are detected in all meristems responsible for development of the aerial part of rice , suggesting that genes sharing functional redundancy with FON1 act in the vegetative and inflorescence meristems to mask the effects of the fon1 mutation . | Matching Sentences:
[ Sen. 6, subscore: 1.00 ]: The regulation of floral organ number is closely associated with floral meristem size . Mutations in the gene FLORAL ORGAN NUMBER1 ( FON1 ) cause enlargement of the floral meristem in Oryza sativa ( rice ) , resulting in an increase in the number of all floral organs . Ectopic floral organs develop in the whorl of each organ and/or in the additional whorls that form . Inner floral organs are more severely affected than outer floral organs . Many carpel primordia develop indeterminately , and undifferentiated meristematic it issues remain in the center in almost-mature flowers . Consistent with this result , OSH1 , a molecular marker of meristematic indeterminate cells in rice , continues to be expressed in this region . Although floral meristems are strongly affected by the fon1-2 mutation , vegetative and inflorescence meristems are largely normal , even in this strong allele . We isolated the FON1 gene by positional cloning and found that it encodes a leucine-rich repeat receptor-like kinase most similar to CLAVATA1 ( CLV1 ) in Arabidopsis thaliana . This suggests that a pathway similar to the CLV signaling system that regulates meristem maintenance in Arabidopsis is conserved in the grass family . Unlike CLV1 , which is predominantly expressed in the L3 layer of the shoot meristem , FON1 is expressed throughout the whole floral meristem , suggesting that small modifications to the CLV signaling pathway may be required to maintain the floral meristem in rice . In addition , FON1 transcripts are detected in all meristems responsible for development of the aerial part of rice , suggesting that genes sharing functional redundancy with FON1 act in the vegetative and inflorescence meristems to mask the effects of the fon1 mutation .
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