SPOROCYTELESS modulates YUCCA expression to regulate the development of lateral organs in Arabidopsis
SPOROCYTELESS modulates YUCCA expression to regulate the development of lateral organs in Arabidopsis
复制标题
DOI：
10.1111/j.1469-8137.2008.02514.x
复制
发表时间：
2008-01-01
期刊：
影响因子：
9.4
通讯作者：
Qu, Li-Jia
中科院分区：
文献类型：
--
作者：
Li, Lin-Chuan;Qin, Gen-Ji;Qu, Li-Jia
生长素在植物生长和发育的许多方面都是必不可少的，包括决定侧边器官的形状。本文报道了拟南芥（Arabidopsis thaliana）显性突变体SPL - d （SPOROCYTELESS dominant）的特征，以及SPL在生长素稳态和植物发育中的作用。SPL - d突变体表现出严重的卷曲叶片表型，这是由SPOROCYTELESS/NOZZLE （SPL/NZZ）的表达增加引起的，SPL/NZZ是一种先前被认为与孢子细胞形成有关的转录因子基因。spld植株也表现出多效性发育缺陷，包括侧根较少、脉序模式较简单和茎尖优势度降低。SPL - d和SPL过表达系的叶片和花表型与丝兰（yuc）三重和四重突变体相似，表明SPL可能调节生长素的稳态。与这一假设相一致的是，我们发现SPL的过表达导致生长素报告基因DR5-GUS的下调，并且许多生长素应答基因在spld叶片中下调。有趣的是，在spld植物中，生长素合成的两个关键基因YUC2和YUC6的表达被显著抑制。结合spll - d / YUC6 - d双突变体的遗传和表型分析，这些数据表明SPL可能通过抑制YUC2和YUC6的转录来调节生长素的稳态，并参与侧壁器官的形态发生。
Auxin is essential for many aspects of plant growth and development, including the determination of lateral organ shapes.Here, the characterization of a dominant Arabidopsis thaliana mutant spl-D (SPOROCYTELESS dominant), and the roles of SPL in auxin homeostasis and plant development, are reported.The spl-D mutant displayed a severe up-curling leaf phenotype caused by increased expression of SPOROCYTELESS/NOZZLE (SPL/NZZ), a putative transcription factor gene that was previously linked to sporocyte formation. The spl-D plants also displayed pleiotropic developmental defects including fewer lateral roots, simpler venation patterns, and reduced shoot apical dominance. The leaf and floral phenotypes of spl-D and SPL over-expression lines were reminiscent of yucca (yuc) triple and quadruple mutants, suggesting that SPL may regulate auxin homeostasis. Consistent with this hypothesis, it was found that over-expression of SPL led to down-regulation of the auxin reporter DR5-GUS, and that many auxin-responsive genes were down-regulated in spl-D leaves. Interestingly, the expression of YUC2 and YUC6, two key genes in auxin biosynthesis, was significantly repressed in spl-D plants.Taken together with the genetic and phenotypic analysis of spl-D/yuc6-D double mutant, these data suggest that SPL may regulate auxin homeostasis by repressing the transcription of YUC2 and YUC6 and participate in lateral organ morphogenesis.