Plant Gene Expression Center, United States Department of Agriculture-Agricultural Research Service/University of California, Berkeley, Albany, California 94710, USA.
Plant Physiol. 2010 Dec;154(4):1721-36. doi: 10.1104/pp.110.163683. Epub 2010 Sep 30.
Intercellular signaling is essential for the coordination of growth and development in higher plants. Although hundreds of putative receptors have been identified in Arabidopsis (Arabidopsis thaliana), only a few families of extracellular signaling molecules have been discovered, and their biological roles are largely unknown. To expand our insight into the developmental processes potentially regulated by ligand-mediated signal transduction pathways, we undertook a systematic expression analysis of the members of the Arabidopsis CLAVATA3/ESR-RELATED (CLE) small signaling polypeptide family. Using reporter constructs, we show that the CLE genes have distinct and specific patterns of promoter activity. We find that each Arabidopsis tissue expresses at least one CLE gene, indicating that CLE-mediated signaling pathways are likely to play roles in many biological processes during the plant life cycle. Some CLE genes that are closely related in sequence have dissimilar expression profiles, yet in many tissues multiple CLE genes have overlapping patterns of promoter-driven reporter activity. This observation, plus the general absence of detectable morphological phenotypes in cle null mutants, suggest that a high degree of functional redundancy exists among CLE gene family members. Our work establishes a community resource of CLE-related biological materials and provides a platform for understanding and ultimately manipulating many different plant signaling systems.
细胞间信号转导对于高等植物的生长和发育协调至关重要。尽管在拟南芥(Arabidopsis thaliana)中已经鉴定了数百种假定的受体,但只发现了少数几种细胞外信号分子家族,它们的生物学功能在很大程度上尚不清楚。为了更深入地了解可能受配体介导的信号转导途径调控的发育过程,我们对拟南芥 CLAVATA3/ESR-RELATED(CLE)小信号多肽家族的成员进行了系统的表达分析。使用报告基因构建体,我们表明 CLE 基因具有独特而特定的启动子活性模式。我们发现每个拟南芥组织都至少表达一种 CLE 基因,表明 CLE 介导的信号通路可能在植物生命周期的许多生物学过程中发挥作用。一些在序列上密切相关的 CLE 基因具有不同的表达谱,但在许多组织中,多个 CLE 基因具有重叠的启动子驱动报告基因活性模式。这种观察结果,加上 cle 缺失突变体中通常没有可检测到的形态表型,表明 CLE 基因家族成员之间存在高度的功能冗余。我们的工作建立了一个与 CLE 相关的生物学材料的社区资源,并为理解和最终操纵许多不同的植物信号系统提供了一个平台。