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Score: 5.00 | | Author: Sato Y Sentoku N Miura Y Hirochika H Kitano H Matsuoka M | Journal: EMBO J Citation: V : 18 ( 4 ) P : 992-1002 Year: 1999 | 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 ]: 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 . [ Sen. 1, subscore: 1.00 ]: The rice homeobox gene OSH15 ( Oryza sativa homeobox ) is a member of the knotted1-type homeobox gene family . [ Sen. 2, subscore: 1.00 ]: 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 . [ Sen. 7, subscore: 1.00 ]: These mutations demonstrate a role for OSH15 in the development of rice internodes .
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Score: 3.00 | | Author: Postma-Haarsma AD Verwoert II Stronk OP Koster J Lamers GE Hoge JH Meijer AH .
| Journal: Plant Mol . Biol . Citation: V : 39 ( 2 ) P : 257-71 Year: 1999 | 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 ]: Two of these , Oskn2 and Oskn3 , encode newly described KNOX genes , whereas the third ( Oskn1 ) corresponds to the previously described OSH1 gene . [ Sen. 6, subscore: 1.00 ]: 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 . [ Sen. 8, subscore: 1.00 ]: 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 .
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Score: 5.00 | | Author: Satoh N Hong SK Nishimura A Matsuoka M Kitano H Nagato Y | Journal: Development Citation: V : 126 ( 16 ) P : 3629-36 Year: 1999 | 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 ]: 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 . [ Sen. 10, subscore: 2.00 ]: Accordingly , SHL1 and SHL2 function upstream of OSH1 , and SHL3 and SHL4 downstream or independently of OSH1 .
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Score: 1.00 | | Author: Itoh JI Kitano H Matsuoka M Nagato Y | Journal: Plant Cell Citation: V : 12 ( 11 ) P : 2161-74 Year: 2000 | 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 ]: 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 .
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Score: 1.00 | | Author: Komatsu M Maekawa M Shimamoto K Kyozuka J | Journal: Dev . Biol . Citation: V : 231 ( 2 ) P : 364-73 Year: 2001 | 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 ]: In situ hybridization analysis using OSH1 , a rice knotted1 ( kn1 ) ortholog , confirmed the absence of lateral meristems in lax1-2 panicles .
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Score: 4.00 | | Author: Ito Y Eiguchi M Kurata N | Journal: Genesis Citation: V : 30 ( 4 ) P : 231-8 Year: 2001 | 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 . [ Sen. 3, subscore: 1.00 ]: 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 .
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Score: 3.00 | | Author: Nagasaki H Sakamoto T Sato Y Matsuoka M | Journal: Plant Cell Citation: V : 13 ( 9 ) P : 2085-98 Year: 2001 | 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 ) . [ Sen. 4, subscore: 1.00 ]: 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 . [ Sen. 6, subscore: 1.00 ]: 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 .
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Score: 1.00 | | Author: Satoh N Itoh J Nagato Y | Journal: Genetics Citation: V : 164 ( 1 ) P : 335-46 Year: 2003 | 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 ]: 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 .
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Score: 2.00 | | Author: Kamiya N Nishimura A Sentoku N Takabe E Nagato Y Kitano H Matsuoka M | Journal: Plant Cell Physiol .
Citation: V : 44 ( 9 ) P : 875-83 Year: 2003 | 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 ]: 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 ) . [ Sen. 5, subscore: 1.00 ]: 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 .
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Score: 1.00 | | Author: Suzaki T Sato M Ashikari M Miyoshi M Nagato Y Hirano HY .
| Journal: Development Citation: V : 131 ( 22 ) P : 5649-57 Year: 2004 | 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 ]: Consistent with this result , OSH1 , a molecular marker of meristematic indeterminate cells in rice , continues to be expressed in this region .
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Score: 1.00 | | Author: Yamaki S Satoh H Nagato Y | Journal: Planta Citation: V : 222 ( 3 ) P : 408-17 Year: 2005 | Literature: oryza Field: abstract Doc ID: pub16001259 Accession (PMID): 16001259 | Abstract: The embryo position in a seed is stable in most plant species , indicating the existence of a strict regulatory mechanism that specifies the embryo position in the seed .
To elucidate this mechanism , we analyzed the gypsy embryo ( gym ) mutant of rice , in which the position of the mature embryo in the seed is altered at a low frequency .
Analyses of early embryogenesis and ovule development showed that the ectopic embryo was derived from an ill-positioned egg cell , which resulted from the incomplete curvature of the ovule .
Although the development of both the inner and outer integuments was impaired , the ovule curvature was associated closely with the extent of inner integument growth .
Therefore , inner integument development controls ovule curvature in rice .
The expression patterns of OSH1 and OsMADS13 indicated that , in gym , a small number of indeterminate cells are maintained on the style side of the ovule and then in the integument primordium at a low frequency .
The prolonged survival of these indeterminate cells disturbs normal integument development .
The gym fon2 double mutant suggests that GYM and FON2 are involved redundantly in floral meristem determinacy .
Possible functions of the GYM gene and the ovule developmental mechanism are discussed . | Matching Sentences: [ Sen. 6, subscore: 1.00 ]: The expression patterns of OSH1 and OsMADS13 indicated that , in gym , a small number of indeterminate cells are maintained on the style side of the ovule and then in the integument primordium at a low frequency .
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Score: 3.00 | | Author: Nagasaki H Matsuoka M Sato Y | Journal: Genes Genet .
Syst Citation: V : 80 ( 4 ) P : 261-7 Year: 2005 | Literature: oryza Field: abstract Doc ID: pub16284419 Accession (PMID): 16284419 | Abstract: Transacting factors often form homo and heterodimers and regulate various targets , the type of regulation depending on the dimeric combination .
The WUS and TALE subfamilies are two atypical homeodomains in plants .
A homeodomain mediates sequence-specific binding to its target DNA and usually consists of 60 amino acid residues , whereas atypical homeodomains have extra amino acid residues in the well-conserved region .
The genes OsWUS and OsPRS , which encode atypical homeodomain proteins from the WUS subfamily , and OsBEL and OSH15 , which encode those from the TALE subfamily , were isolated from rice and tested for their interactions by yeast two-hybrid analysis .
OsWUS and OsPRS formed homodimers and formed heterodimers with each other but did not form dimers with the TALE family homeodomain proteins OSH15 or OsBEL .
Likewise , OSH15 and OsBEL formed homodimers and heterodimers but did not form dimers with the WUS family homeodomain proteins OsWUS and OsPRS .
These findings suggest that the combinations of dimers are well correlated with the classification of these proteins on the basis of sequence similarity .
RT-PCR analysis revealed that expression of OsWUS and OsPRS was detected in the same organs , namely floral buds , roots , and suspension cells .
Therefore , it is possible that the proteins encoded by both of these genes function as homo and heterodimers in planta .
These results suggest that , during the evolution of these subfamilies , various combinations of dimers within proteins encoded by paralogous genes were formed and generated independent regulatory networks that enabled complex patterns of plant development . | Matching Sentences: [ Sen. 4, subscore: 1.00 ]: The genes OsWUS and OsPRS , which encode atypical homeodomain proteins from the WUS subfamily , and OsBEL and OSH15 , which encode those from the TALE subfamily , were isolated from rice and tested for their interactions by yeast two-hybrid analysis . [ Sen. 5, subscore: 1.00 ]: OsWUS and OsPRS formed homodimers and formed heterodimers with each other but did not form dimers with the TALE family homeodomain proteins OSH15 or OsBEL . [ Sen. 6, subscore: 1.00 ]: Likewise , OSH15 and OsBEL formed homodimers and heterodimers but did not form dimers with the WUS family homeodomain proteins OsWUS and OsPRS .
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Score: 1.00 | | Author: Jouannic S Collin M Vidal B Verdeil JL Tregear JW | Journal: New Phytol Citation: V : 174 P : 551-68 Year: 2007 | Literature: oryza Field: abstract Doc ID: pub17447911 Accession (PMID): 17447911 | Abstract: Class I Knotted-like homeobox ( KNOX ) transcription factors are important regulators of shoot apical meristem function and leaf morphology by their contribution to dissected leaf development .
Palms are of particular interest as they produce dissected leaves generated by a distinct mechanism compared with eudicots .
The question addressed here was whether class I KNOX genes might be involved in meristem function and leaf dissection in palms .
Here , we characterized the EgKNOX1 gene from oil palm ( Elaeis guineensis , Arecaceae ) and compared it with available sequences from other plant species using phylogenetic analysis .
Gene expression pattern was investigated using reverse transcription-polymerase chain reaction ( RT-PCR ) and in situ hybridization .
Functional analysis was carried out by ectopic expression in Arabidopsis and rice .
EgKNOX1 was orthologous to STM from Arabidopsis and to OSH1 from rice .
It was expressed in the central zone of both vegetative and reproductive meristems .
During leaf development , its expression was associated with plications from which the leaflets originate .
Different modes of leaf dissection are seen to involve a similar class of genes to control meristematic activities , which govern the production of dissected morphologies .
| Matching Sentences: [ Sen. 7, subscore: 1.00 ]: EgKNOX1 was orthologous to STM from Arabidopsis and to OSH1 from rice .
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Score: 1.00 | | Author: Sazuka T Kamiya N Nishimura T Ohmae K Sato Y Imamura K Nagato Y Koshiba T Nagamura Y Ashikari M Kitano H Matsuoka M | Journal: Plant J Citation: V : 60 P : 227-41 Year: 2009 | Literature: oryza Field: abstract Doc ID: pub19682283 Accession (PMID): 19682283 | Abstract: Indole-3-acetic acid ( IAA ) plays a critical role in many aspects of plant growth and development ; however , complete pathways of biosynthesis , localization and many aspects of functions of IAA in rice remain unclear .
Here , we report the analysis of a rice tryptophan ( Trp- ) and IAA-deficient mutant , tryptophan deficient dwarf1 ( tdd1 ) , which is embryonic lethal because of a failure to develop most organs during embryogenesis .
Regenerated tdd1 plants showed pleiotropic phenotypes : dwarfing , narrow leaves , short roots and abnormal flowers .
TDD1 encodes a protein homologous to anthranilate synthase beta-subunit , which catalyses the first step of the Trp biosynthesis pathway and functions upstream of Trp-dependent IAA biosynthesis .
TDD1-uidA and DR5-uidA expression overlapped at many sites in WT plants but was lacking in tdd1 , indicating that TDD1 is involved in auxin biosynthesis .
Both Trp and IAA levels in flowers and embryos were much lower in tdd1 than in wild type ( WT ) .
Trp feeding completely rescued the mutant phenotypes and moderate expression of OsYUCCA1 , which encodes a key enzyme in Trp-dependent IAA biosynthesis , also rescued plant height and root length , indicating that the abnormal phenotypes of tdd1 are caused predominantly by Trp and IAA deficiency .
In tdd1 embryos , the expression patterns of OSH1 and OsSCR , which mark the presumptive apical region and the L2 layer , respectively , are identical to those in WT , suggesting a possibility either that different IAA levels are required for basic pattern formation than for organ formation or that an orthologous gene compensates for TDD1 deficiency during pattern formation .
| Matching Sentences: [ Sen. 8, subscore: 1.00 ]: In tdd1 embryos , the expression patterns of OSH1 and OsSCR , which mark the presumptive apical region and the L2 layer , respectively , are identical to those in WT , suggesting a possibility either that different IAA levels are required for basic pattern formation than for organ formation or that an orthologous gene compensates for TDD1 deficiency during pattern formation .
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Score: 8.00 | | Author: Tsuda K Ito Y Sato Y Kurata N | Journal: Plant Cell Citation: V : P : Year: 2011 | Literature: oryza Field: abstract Doc ID: pub22207572 Accession (PMID): 22207572 | Abstract: Self-maintenance of the shoot apical meristem ( SAM ) , from which aerial organs are formed throughout the life cycle , is crucial in plant development .
Class I Knotted1-like homeobox ( KNOX ) genes restrict cell differentiation and play an indispensable role in maintaining the SAM .
However , the mechanism that positively regulates their expression is unknown .
Here , we show that expression of a rice ( Oryza sativa ) KNOX gene , Oryza sativa homeobox1 ( OSH1 ) , is positively regulated by direct autoregulation .
Interestingly , loss-of-function mutants of OSH1 lose the SAM just after germination but can be rescued to grow until reproductive development when they are regenerated from callus .
Double mutants of osh1 and d6 , a loss-of-function mutant of OSH15 , fail to establish the SAM both in embryogenesis and regeneration .
Expression analyses in these mutants reveal that KNOX gene expression is positively regulated by the phytohormone cytokinin and by KNOX genes themselves .
We demonstrate that OSH1 directly binds to five KNOX loci , including OSH1 and OSH15 , through evolutionarily conserved cis-elements and that the positive autoregulation of OSH1 is indispensable for its own expression and SAM maintenance .
Thus , the maintenance of the indeterminate state mediated by positive autoregulation of a KNOX gene is an indispensable mechanism of self-maintenance of the SAM .
| Matching Sentences: [ Sen. 8, subscore: 4.00 ]: We demonstrate that OSH1 directly binds to five KNOX loci , including OSH1 and OSH15 , through evolutionarily conserved cis-elements and that the positive autoregulation of OSH1 is indispensable for its own expression and SAM maintenance . [ Sen. 6, subscore: 2.00 ]: Double mutants of osh1 and d6 , a loss-of-function mutant of OSH15 , fail to establish the SAM both in embryogenesis and regeneration . [ Sen. 4, subscore: 1.00 ]: Here , we show that expression of a rice ( Oryza sativa ) KNOX gene , Oryza sativa homeobox1 ( OSH1 ) , is positively regulated by direct autoregulation . [ Sen. 5, subscore: 1.00 ]: Interestingly , loss-of-function mutants of OSH1 lose the SAM just after germination but can be rescued to grow until reproductive development when they are regenerated from callus .
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Score: 1.00 | | Author: Dockx J Quaedvlieg N Keultjes G Kock P Weisbeek P Smeekens S | Journal: Plant Mol . Biol . Citation: V : 28 ( 4 ) P : 723-37 Year: 1995 | Literature: oryza Field: abstract Doc ID: pub7647303 Accession (PMID): 7647303 | Abstract: The homeodomain is a DNA-binding domain present in a large family of eukaryotic regulatory proteins .
Homeodomain proteins have been shown to play key roles in controlling developmental programs in various organisms .
Here we report the isolation and characterisation of a homeobox gene from Arabidopsis thaliana designated ATK1 .
The gene was isolated using as a probe the homeobox domain of the KN1 gene from maize .
The homeodomain of ATK1 is highly homologous to the homeodomain of the KN1 gene of maize ( 81% ) but shows only poor homology outside the homeodomain .
Therefore ATK1 is probably not the Arabidopsis homologue of the KN1 gene from maize .
It contains the four invariant amino acid residues present in the recognition helix 3 of all other homeodomain proteins .
Outside the homeodomain a region rich in aspartate and glutamate residues is found suggesting that ATK1 is a transcriptional activator .
The gene contains four introns which is similar in the KN1 gene of maize and the Osh1 gene of rice .
Primer extension reveals the presence of two transcription initiation sites .
The leader sequence of the genuine transcript is 342 nucleotides long and contains two upstream open reading frames .
ATK1 is strongly expressed in the shoot apex of seedlings , while in mature plants the gene is primarily expressed in flowers and inflorescence stems .
Such an expression pattern is reminiscent of that of the KN1 gene of maize and therefore ATK1 could similarly be involved in determining cell fate .
| Matching Sentences: [ Sen. 9, subscore: 1.00 ]: The gene contains four introns which is similar in the KN1 gene of maize and the Osh1 gene of rice .
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Score: 6.00 | | Author: Kano-Murakami Y Yanai T Tagiri A Matsuoka M | Journal: FEBS Lett .
Citation: V : 334 ( 3 ) P : 365-8 Year: 1993 | Literature: oryza Field: abstract Doc ID: pub7902297 Accession (PMID): 7902297 | Abstract: A rice gene , OSH1 , which shares homology with animal homeobox genes , has been isolated .
We have introduced the OSH1 cDNA into tobacco in order to examine its function .
Expression of the OSH1 cDNA in tobacco induced morphological abnormalities in the leaves , petals and stems of the transformants suggesting that OSH1 functions as a morphological regulator .
OSH1 cDNA expression was analyzed under the control of three different promoters .
This work revealed that not only the level of OSH1 expression but also the site and timing of the expression affect the morphology of the plant . | Matching Sentences: [ Sen. 3, subscore: 2.00 ]: Expression of the OSH1 cDNA in tobacco induced morphological abnormalities in the leaves , petals and stems of the transformants suggesting that OSH1 functions as a morphological regulator . [ Sen. 1, subscore: 1.00 ]: A rice gene , OSH1 , which shares homology with animal homeobox genes , has been isolated . [ Sen. 2, subscore: 1.00 ]: We have introduced the OSH1 cDNA into tobacco in order to examine its function . [ Sen. 4, subscore: 1.00 ]: OSH1 cDNA expression was analyzed under the control of three different promoters . [ Sen. 5, subscore: 1.00 ]: This work revealed that not only the level of OSH1 expression but also the site and timing of the expression affect the morphology of the plant .
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Score: 10.00 | | Author: Matsuoka M Ichikawa H Saito A Tada Y Fujimura T Kano-Murakami Y | Journal: Plant Cell Citation: V : 5 ( 9 ) P : 1039-48 Year: 1993 | Literature: oryza Field: abstract Doc ID: pub8104574 Accession (PMID): 8104574 | Abstract: We have isolated a cDNA clone encoding a homeobox sequence from rice .
DNA sequence analysis of this clone , which was designated as Oryza sativa homeobox 1 ( OSH1 ) , and a genomic clone encoding the OSH1 sequence have shown that the OSH1 gene consists of five exons and encodes a polypeptide of 361 amino acid residues .
Restriction fragment length polymorphism analysis has shown that OSH1 is a single-copy gene located near the phytochrome gene on chromosome 3 .
Introduction of the cloned OSH1 gene into rice resulted in altered leaf morphology , which was similar to that of the maize morphological mutant Knotted-1 ( Kn1 ) , indicating that OSH1 is a rice gene homologous to the maize Kn1 gene .
RNA gel blot analysis has shown that the gene is primarily expressed in the shoot apices of young rice seedlings .
This finding is supported by results of transformation experiments in which the 5 flanking region of the gene directed expression of a reporter gene in the shoot apex , particularly in stipules , of transgenic Arabidopsis .
To elucidate the biological function of the OSH1 gene product , the coding region was introduced into Arabidopsis under the control of the cauliflower mosaic virus 35S promoter .
Almost all transformants showed abnormal morphology .
The typical phenotype was the formation of clumps of abundant vegetative and reproductive shoot apices containing meristems and leaf primordia , which did not form elongated shoots .
Some transformants with a less severe phenotype formed elongated shoots but had abnormally shaped leaves and flowers with stunted sepals , petals , and stamens .
The abnormal phenotypes were inherited , and the level of expression of the introduced OSH1 correlates with the severity of the phenotype .
These findings indicate that the abnormal morphologies of the transgenic plants are caused by the expression of the OSH1 gene product and , therefore , that OSH1 is related to the plant development process . | Matching Sentences: [ Sen. 2, subscore: 3.00 ]: DNA sequence analysis of this clone , which was designated as Oryza sativa homeobox 1 ( OSH1 ) , and a genomic clone encoding the OSH1 sequence have shown that the OSH1 gene consists of five exons and encodes a polypeptide of 361 amino acid residues . [ Sen. 4, subscore: 2.00 ]: Introduction of the cloned OSH1 gene into rice resulted in altered leaf morphology , which was similar to that of the maize morphological mutant Knotted-1 ( Kn1 ) , indicating that OSH1 is a rice gene homologous to the maize Kn1 gene . [ Sen. 12, subscore: 2.00 ]: These findings indicate that the abnormal morphologies of the transgenic plants are caused by the expression of the OSH1 gene product and , therefore , that OSH1 is related to the plant development process . [ Sen. 3, subscore: 1.00 ]: Restriction fragment length polymorphism analysis has shown that OSH1 is a single-copy gene located near the phytochrome gene on chromosome 3 . [ Sen. 7, subscore: 1.00 ]: To elucidate the biological function of the OSH1 gene product , the coding region was introduced into Arabidopsis under the control of the cauliflower mosaic virus 35S promoter . [ Sen. 11, subscore: 1.00 ]: The abnormal phenotypes were inherited , and the level of expression of the introduced OSH1 correlates with the severity of the phenotype .
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Score: 1.00 | | Author: Tamaoki M Ichikawa H Kayano T Kano-Murakami Y Yamamoto N Matsuoka M | Journal: Biochem . Biophys . Res . Commun . Citation: V : 221 ( 2 ) P : 408-13 Year: 1996 | Literature: oryza Field: abstract Doc ID: pub8619869 Accession (PMID): 8619869 | Abstract: A rice homeobox gene , OSH1 , contains two functionally independent promoters which generate a larger transcript and a smaller transcript .
In Arabidopsis , each promoter can drive the expression of a reporter gene in a different manner , indicating that the expression of different sized transcripts is independently regulated by each promoter .
Over-expression of the larger transcript in transformed plants caused altered morphologies ( Matsuoka et al , Plant Cell , 1993 , 5 , 1039-1048 ) ; in contrast , over-expression of the smaller transcript did not cause any morphological changes .
The results suggest that the product of the smaller transcript fails to alter the expression of its target gene ( s ) in the transformants , while that of the larger transcript is capable of altering the expression of its target gene ( s ) . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: A rice homeobox gene , OSH1 , contains two functionally independent promoters which generate a larger transcript and a smaller transcript .
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Score: 4.00 | | Author: Sato Y Tamaoki M Murakami T Yamamoto N Kano-Murakami Y Matsuoka M | Journal: Mol . Gen . Genet . Citation: V : 251 ( 1 ) P : 13-22 Year: 1996 | Literature: oryza Field: abstract Doc ID: pub8628242 Accession (PMID): 8628242 | Abstract: Transgenic tobacco plants were generated carrying a rice homeobox gene , OSH1 , controlled by the promoter of a gene encoding a tobacco pathogenesis-related protein ( PR1a ) .
These lines were morphologically abnormal , with wrinkled and/or lobed leaves .
Histological analysis of shoot apex primordia indicates arrest of lateral leaf blade expansion , often resulting in asymmetric and anisotrophic growth of leaf blades .
Other notable abnormalities included abnormal or arrested development of leaf lateral veins .
Interestingly , OHS1 expression was undetectable in mature leaves with the aberrant morphological features .
Thus , OSH1 expression in mature leaves is not necessary for abnormal leaf development .
Northern blot and in situ hybridization analyses indicate that PR1a-OSH1 is expressed only in the shoot apical meristem and in very young leaf primordia .
Therefore , the aberrant morphological features are an indirect consequence of ectopic OSH1 gene expression .
The only abnormality observed in it issues expressing the transgene was periclinal ( rather than anticlinal ) division in mesophyll cells during leaf blade initiation .
This generates thicker leaf blades and disrupts the mesophyll cell layers , from which vascular it issues differentiate .
The OSH1 product appears to affect the mechanism controlling the orientation of the plane of cell division , resulting in abnormal periclinal division of mesophyll cell , which in turn results in the gross morphological abnormalities observed in the transgenic lines . | Matching Sentences: [ Sen. 1, subscore: 1.00 ]: Transgenic tobacco plants were generated carrying a rice homeobox gene , OSH1 , controlled by the promoter of a gene encoding a tobacco pathogenesis-related protein ( PR1a ) . [ Sen. 6, subscore: 1.00 ]: Thus , OSH1 expression in mature leaves is not necessary for abnormal leaf development . [ Sen. 8, subscore: 1.00 ]: Therefore , the aberrant morphological features are an indirect consequence of ectopic OSH1 gene expression . [ Sen. 11, subscore: 1.00 ]: The OSH1 product appears to affect the mechanism controlling the orientation of the plane of cell division , resulting in abnormal periclinal division of mesophyll cell , which in turn results in the gross morphological abnormalities observed in the transgenic lines .
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