Dataset Information

CsAP3: A Cucumber Homolog to Arabidopsis APETALA3 with Novel Characteristics.

ABSTRACT: In our previous efforts to understand the regulatory mechanisms of cucumber unisexual flower development, we observed a stamen-specific down-regulation of the ethylene receptor CsETR1 in stage 6 female flowers of cucumber (Cucumis sativus L.). This down-regulation is correlated with the primordial anther-specific DNA damage that characterizes inappropriate stamen development in cucumber female flowers. To understand how CsETR1 is down regulated in the stamen, we characterized a cucumber MADS box gene homologous to Arabidopsis AP3, CsAP3. We demonstrated that CsAP3 is functionally equivalent to the Arabidopsis B-class MADS gene AP3. However, three novel characteristics of CsAP3 were found. These include firstly, binding and activating CsETR1 promoter in vitro and in vivo; secondly, containing a GV repeat in its C-terminus, which is conserved in cucurbits and required for the transcription activation; and thirdly, decreased expression as the node number increases, which is similar to that found for CsETR1. These findings revealed not only the conserved function of CsAP3 as a B-class floral identity gene, but also its unique functions in regulation of female flower development in cucumber.

SUBMITTER: Sun JJ

PROVIDER: S-EPMC4972961 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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CsAP3: A Cucumber Homolog to Arabidopsis APETALA3 with Novel Characteristics.

Sun Jin-Jing JJ Li Feng F Wang Dong-Hui DH Liu Xiao-Feng XF Li Xia X Liu Na N Gu Hai-Tao HT Zou Cheng C Luo Jing-Chu JC He Chao-Xing CX Huang San-Wen SW Zhang Xiao-Lan XL Xu Zhi-Hong ZH Bai Shu-Nong SN

Frontiers in plant science 20160804

In our previous efforts to understand the regulatory mechanisms of cucumber unisexual flower development, we observed a stamen-specific down-regulation of the ethylene receptor CsETR1 in stage 6 female flowers of cucumber (Cucumis sativus L.). This down-regulation is correlated with the primordial anther-specific DNA damage that characterizes inappropriate stamen development in cucumber female flowers. To understand how CsETR1 is down regulated in the stamen, we characterized a cucumber MADS box ...[more]

PMID: 27540391

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Dataset Information

CsAP3: A Cucumber Homolog to Arabidopsis APETALA3 with Novel Characteristics.

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CsAP3: A Cucumber Homolog to Arabidopsis APETALA3 with Novel Characteristics.

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