Department of Biology, Stanford University, Stanford, California 94305-5020, USA.
Plant Cell. 2011 Aug;23(8):2864-79. doi: 10.1105/tpc.111.086637. Epub 2011 Aug 23.
Core signaling pathways function in multiple programs during multicellular development. The mechanisms that compartmentalize pathway function or confer process specificity, however, remain largely unknown. In Arabidopsis thaliana, ERECTA (ER) family receptors have major roles in many growth and cell fate decisions. The ER family acts with receptor TOO MANY MOUTHS (TMM) and several ligands of the EPIDERMAL PATTERNING FACTOR LIKE (EPFL) family, which play distinct yet overlapping roles in patterning of epidermal stomata. Here, our examination of EPFL genes EPFL6/CHALLAH (CHAL), EPFL5/CHALLAH-LIKE1, and EPFL4/CHALLAH-LIKE2 (CLL2) reveals that this family may mediate additional ER-dependent processes. chal cll2 mutants display growth phenotypes characteristic of er mutants, and genetic interactions are consistent with CHAL family molecules acting as ER family ligands. We propose that different classes of EPFL genes regulate different aspects of ER family function and introduce a TMM-based discriminatory mechanism that permits simultaneous, yet compartmentalized and distinct, function of the ER family receptors in growth and epidermal patterning.
核心信号通路在多细胞发育的多个程序中发挥作用。然而，将途径功能分隔或赋予过程特异性的机制在很大程度上仍然未知。在拟南芥中，ERECTA（ER）家族受体在许多生长和细胞命运决定中起主要作用。ER 家族与受体 TOO MANY MOUTHS（TMM）和表皮模式形成因子样（EPFL）家族的几个配体一起发挥作用，这些配体在表皮气孔的模式形成中发挥着不同但重叠的作用。在这里，我们对 EPFL 基因 EPFL6/CHALLAH（CHAL）、EPFL5/CHALLAH-LIKE1 和 EPFL4/CHALLAH-LIKE2（CLL2）的研究表明，该家族可能介导额外的 ER 依赖性过程。chal cll2 突变体表现出与 er 突变体相似的生长表型，遗传相互作用与 CHAL 家族分子作为 ER 家族配体的作用一致。我们提出，不同类别的 EPFL 基因调节 ER 家族功能的不同方面，并引入了一种基于 TMM 的鉴别机制，允许 ER 家族受体在生长和表皮模式形成中同时但分隔和独特地发挥作用。
