Liu Tie, Ohashi-Ito Kyoko, Bergmann Dominique C
Biology Department, 371 Serra Mall, Stanford University, Stanford, CA 94305-5020, USA.
Development. 2009 Jul;136(13):2265-76. doi: 10.1242/dev.032938.
Stomata are adjustable pores in the plant epidermis that regulate gas exchange between the plant and atmosphere; they are present on the aerial portions of most higher plants. Genetic pathways controlling stomatal development and distribution have been described in some detail for one dicot species, Arabidopsis, in which three paralogous bHLH transcription factors, FAMA, MUTE and SPCH, control discrete sequential stages in stomatal development. Orthologs of FAMA, MUTE and SPCH are present in other flowering plants. This observation is of particular interest when considering the grasses, because both the morphology of guard cells and their tissue distributions differ substantially between Arabidopsis and this group. By examining gene expression patterns, insertional mutants and cross-species complementation studies, we find evidence that FAMA function is conserved between monocots and dicots, despite their different stomatal morphologies, whereas the roles of MUTE and two SPCH paralogs are somewhat divergent.
气孔是植物表皮中可调节的孔隙，用于调节植物与大气之间的气体交换；它们存在于大多数高等植物的地上部分。对于一种双子叶植物拟南芥，控制气孔发育和分布的遗传途径已得到较为详细的描述，其中三个同源的bHLH转录因子FAMA、MUTE和SPCH控制气孔发育的离散连续阶段。FAMA、MUTE和SPCH的直系同源物存在于其他开花植物中。在考虑禾本科植物时，这一观察结果尤为有趣，因为拟南芥与该类群的保卫细胞形态及其组织分布存在很大差异。通过检查基因表达模式、插入突变体和跨物种互补研究，我们发现证据表明，尽管单子叶植物和双子叶植物的气孔形态不同，但FAMA的功能在它们之间是保守的，而MUTE和两个SPCH旁系同源物的作用则有些不同。
