The BIG gene is required for auxin-mediated organ growth in Arabidopsis
The BIG gene is required for auxin-mediated organ growth in Arabidopsis
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拟南芥中生长素介导的器官生长需要 BIG 基因
DOI：
10.1007/s00425-012-1834-4
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发表时间：
2013-04-01
期刊：
影响因子：
4.3
通讯作者：
Hou, Suiwen
中科院分区：
文献类型：
--
作者：
Guo, Xiaola;Lu, Wenwen;Hou, Suiwen
通过细胞扩增和细胞增殖控制器官大小是发育过程中的一个基本过程，但BIG在这一过程中的重要性仍然知之甚少。在这里，我们报告的分离和一个新的等位基因突变体的拟南芥BIG：big-j588的特性。突变体显示小的气生器官，其特征在于减少细胞大小的表皮和短根细胞数量减少。big-j588 axr 1双突变体和big-j588 arf 7 arf 19三突变体在叶片扩展和根伸长方面表现出比它们的亲本更严重的缺陷，这意味着BIG参与了生长素依赖的器官生长。遗传分析表明，BIG可能与PIN 1协同作用，影响叶片生长。pIN 1蛋白在big-j588的根细胞和叶面细胞叶尖中的表达水平均下降。进一步的分析表明，big-j588根和叶中的最大生长素含量下降。因此，我们认为big-j588的小叶片和短根与生长素的减少有关。总之，我们的研究表明，BIG是拟南芥器官生长所需的生长素行动。
Control of organ size by cell expansion and cell proliferation is a fundamental process during development, but the importance of BIG in this process is still poorly understood. Here, we report the isolation and characterization of a new allele mutant of BIG in Arabidopsis: big-j588. The mutant displayed small aerial organs that were characterized by reduced cell size in the epidermis and short roots with decreased cell numbers. The big-j588 axr1 double and big-j588 arf7 arf19 triple mutants displayed more severe defects in leaf expansion and root elongation than their parents, implying BIG is involved in auxin-dependent organ growth. Genetic analysis suggests that BIG may act synergistically with PIN1 to affect leaf growth. The PIN1 protein level decreased in both the root cells and the tips of leaf pavement cell lobes of big-j588. Further analysis showed that the auxin maxima in the roots and the leaves of big-j588 decreased. Therefore, we concluded that the small leaves and the short roots of big-j588 were associated with reduction of auxin maxima. Overall, our study suggested that BIG is required for Arabidopsis organ growth via auxin action.