Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK.
New Phytol. 2010 May;186(3):609-14. doi: 10.1111/j.1469-8137.2010.03200.x. Epub 2010 Feb 10.
The putative secretory peptides epidermal patterning factor 1 (EPF1) and EPF2 act as negative regulators of stomatal clustering and density early in Arabidopsis leaf development. Here, we investigated whether the related peptide gene epidermal patterning factor-like 9 (EPFL9), which is coexpressed with EPF1 and stomatal density and distribution 1 (SDD1), also plays a role in controlling stomatal development. Plants manipulated to constitutively overexpress EPFL9 showed increased stomatal density and clustering, and those manipulated to have reduced EPFL9 expression showed reduced stomatal density with no clustering, confirming that EPFL9 is a regulator of stomatal development. Genetic analysis was consistent with EPFL9 acting independently of EPF1 to control stomatal clustering, independently of EPF2 to regulate stomatal density, and independently of SDD1 to control both stomatal clustering and density. These findings demonstrate that at least three secretory peptides independently regulate stomatal development. Surprisingly, EPFL9 acts to increase, rather than decrease, stomatal density and clustering. However, in common with EPF1 and EPF2, EPFL9 is unlikely to be a substrate for proteolysis by SDD1.
假定的分泌肽表皮模式因子 1（EPF1）和 EPF2 作为拟南芥叶片发育早期气孔簇集和密度的负调控因子。在这里，我们研究了与 EPF1 共表达且与气孔密度和分布 1（SDD1）相关的肽基因表皮模式因子样 9（EPFL9）是否也在控制气孔发育中发挥作用。过表达 EPFL9 的植物表现出气孔密度增加和簇集，而降低 EPFL9 表达的植物表现出气孔密度降低但无簇集，证实 EPFL9 是气孔发育的调节剂。遗传分析与 EPFL9 独立于 EPF1 控制气孔簇集、独立于 EPF2 调节气孔密度以及独立于 SDD1 控制气孔簇集和密度的结果一致。这些发现表明，至少有三种分泌肽独立调节气孔发育。令人惊讶的是，EPFL9 作用于增加而不是减少气孔密度和簇集。然而，与 EPF1 和 EPF2 一样，EPFL9 不太可能成为 SDD1 蛋白水解的底物。
