TY - JOUR
T1 - Conservation and diversification of meristem maintenance mechanism in Oryza sativa
T2 - Function of the FLORAL ORGAN NUMBER2 gene
AU - Suzaki, Takuya
AU - Toriba, Taiyo
AU - Fujimoto, Masaru
AU - Tsutsumi, Nobuhiro
AU - Kitano, Hidemi
AU - Hirano, Hiro Yuki
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2006/12
Y1 - 2006/12
N2 - To elucidate the genetic mechanism that regulates meristem maintenance in monocots, here we have examined the function of the gene FLORAL ORGAN NUMBER2 (FON2) in Oryza sativa (rice). Mutations in FON2 cause enlargement of the floral meristem, resulting in an increase in the number of floral organs, although the vegetative and inflorescence meristems are largely normal. Molecular cloning reveals that FON2 encodes a small secreted protein, containing a CLE domain, that is closely related to CLAVATA3 in Arabidopsis thaliana. FON2 transcripts are localized at the apical region in all meristems in the aerial parts of rice plants, showing an expression pattern similar to that of Arabidopsis CLV3. Constitutive expression of FON2 causes a reduction in the number of floral organs and flowers, suggesting that both the flower and inflorescence meristems are reduced in size. This action of FON2 requires the function of FON1, an ortholog of CLV1. Constitutive expression of FON2 also causes premature termination of the shoot apical meristem in Arabidopsis, a phenotype similar to that caused by constitutive expression of CLV3. Together with our previous study of FON1, these results clearly indicate that the FON1-FON2 system in rice corresponds to the CLV signaling system in Arabidopsis and suggest that the negative regulation of stem cell identity by these systems may be principally conserved in a wide range of plants within the Angiosperms. In addition, we propose a model of the genetic regulation of meristem maintenance in rice that includes an alternative pathway independent of FON2-FON1.
AB - To elucidate the genetic mechanism that regulates meristem maintenance in monocots, here we have examined the function of the gene FLORAL ORGAN NUMBER2 (FON2) in Oryza sativa (rice). Mutations in FON2 cause enlargement of the floral meristem, resulting in an increase in the number of floral organs, although the vegetative and inflorescence meristems are largely normal. Molecular cloning reveals that FON2 encodes a small secreted protein, containing a CLE domain, that is closely related to CLAVATA3 in Arabidopsis thaliana. FON2 transcripts are localized at the apical region in all meristems in the aerial parts of rice plants, showing an expression pattern similar to that of Arabidopsis CLV3. Constitutive expression of FON2 causes a reduction in the number of floral organs and flowers, suggesting that both the flower and inflorescence meristems are reduced in size. This action of FON2 requires the function of FON1, an ortholog of CLV1. Constitutive expression of FON2 also causes premature termination of the shoot apical meristem in Arabidopsis, a phenotype similar to that caused by constitutive expression of CLV3. Together with our previous study of FON1, these results clearly indicate that the FON1-FON2 system in rice corresponds to the CLV signaling system in Arabidopsis and suggest that the negative regulation of stem cell identity by these systems may be principally conserved in a wide range of plants within the Angiosperms. In addition, we propose a model of the genetic regulation of meristem maintenance in rice that includes an alternative pathway independent of FON2-FON1.
KW - CLAVATA signaling pathway
KW - CLE domain
KW - FLORAL ORGAN NUMBER (FON) gene
KW - Meristem maintenance
KW - Oryza sativa (rice)
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U2 - 10.1093/pcp/pcl025
DO - 10.1093/pcp/pcl025
M3 - Article
C2 - 17056620
AN - SCOPUS:33845720355
VL - 47
SP - 1591
EP - 1602
JO - Plant and Cell Physiology
JF - Plant and Cell Physiology
SN - 0032-0781
IS - 12
ER -