BBX32, an Arabidopsis B-Box Protein, Functions in Light Signaling by Suppressing HY5-Regulated Gene Expression and Interacting with STH2/BBX21
BBX32, an Arabidopsis B-Box Protein, Functions in Light Signaling by Suppressing HY5-Regulated Gene Expression and Interacting with STH2/BBX21
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DOI：
10.1104/pp.111.177139
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发表时间：
2011-08-01
期刊：
影响因子：
7.4
通讯作者：
Khanna, Rajnish
中科院分区：
文献类型：
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作者：
Holtan, Hans E.;Bandong, Simona;Khanna, Rajnish
在拟南芥（Arabidopsis thaliana）的大规模功能基因组学研究中，B-box 锌指蛋白 B-BOX32 (BBX32) 被确定在确定下胚轴长度方面发挥着作用。进一步的分析表明，过度表达 BBX32 的幼苗在红光、远红光和蓝光下表现出伸长的下胚轴，同时在红光下表现出子叶扩张减少。通过对突变体和过表达系表型的比较分析，包括全局表达谱和生长曲线研究，我们证明 BBX32 与 ELONGATED HYPOCOTYL5 (HY5) 具有拮抗作用。我们进一步证明 BBX32 与 SALT TOLERANCE HOMOLOG2/BBX21 相互作用，后者是先前显示与 HY5 相互作用的另一种 B-box 蛋白。基于这些数据，我们提出 BBX32 在多个光感受器的下游发挥光响应调制器的作用。因此，BBX32 可能在介导基因抑制以维持暗适应方面发挥天然作用。
A B-box zinc finger protein, B-BOX32 (BBX32), was identified as playing a role in determining hypocotyl length during a large-scale functional genomics study in Arabidopsis (Arabidopsis thaliana). Further analysis revealed that seedlings overexpressing BBX32 display elongated hypocotyls in red, far-red, and blue light, along with reduced cotyledon expansion in red light. Through comparative analysis of mutant and overexpression line phenotypes, including global expression profiling and growth curve studies, we demonstrate that BBX32 acts antagonistically to ELONGATED HYPOCOTYL5 (HY5). We further show that BBX32 interacts with SALT TOLERANCE HOMOLOG2/BBX21, another B-box protein previously shown to interact with HY5. Based on these data, we propose that BBX32 functions downstream of multiple photoreceptors as a modulator of light responses. As such, BBX32 potentially has a native role in mediating gene repression to maintain dark adaptation.