FONf, an Arabidopsis Gene That Terminates Floral Meristem Activity and Controls Flower Organ Number
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چکیده
A novel gene that regulates floral meristem activity and controls floral organ number was identified in Arabidopsis and is designated FONl (for FLORAL QRGAN NUMBERl). The fonl mutants exhibit normal vegetative development and produce normal inflorescence meristems and immature flowers before stage 6. fonl flowers become visibly different from wild-type flowers at stage 6, when the third-whorl stamen primordia have formed. The fonl floral meristem functions longer than does that of the wild type: after the outer three-whorl organ primordia have initiated, the remaining central floral meristem continues to produce additional stamen primordia interior to the third whorl. Prolonged fonl floral meristem activity also results in an increased number of carpels. The clavata (clv) mutations are known to affect floral meristem activity. We have analyzed the c l v l fonl, clv2 fonl, and clv3 fonl double mutants. These double mutants all have similar phenotypes, with more stamens and carpels than either fonl or clv single mutants. This indicates that FONl and CLW genes function in different pathways to control the number of thirdand fourth-whorl floral organs. In addition, to test for possible interactions between FONl and other floral regulatory genes, we have constructed and analyzed the relevant double mutants. Our results suggest that FONl does not interact with TERMlNAL FLOWERl, APETALAl, APETALAP, or UNUSUAL FLORAL ORGAN. In contrast, normal LEAFYfunction is required for the expression of fonl phenotypes. In addition, FONl and AGAMOUS both seem to affect the domain of APETALA3 function, which also affects the formation of stamen-carpel chimera due to fonl mutations. Finally, genetic analysis suggests that FONl interacts with SUPERMAN, which also regulates floral meristem activity.
منابع مشابه
FON1, an Arabidopsis gene that terminates floral meristem activity and controls flower organ number.
A novel gene that regulates floral meristem activity and controls floral organ number was identified in Arabidopsis and is designated FON1 (for FLORAL ORGAN NUMBER1). The fon1 mutants exhibit normal vegetative development and produce normal inflorescence meristems and immature flowers before stage 6. fon1 flowers become visibly different from wild-type flowers at stage 6, when the third-whorl s...
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