Yang M, Sack F D
Department of Plant Biology, Ohio State University, Columbus 43210-1293, USA.
Plant Cell. 1995 Dec;7(12):2227-39. doi: 10.1105/tpc.7.12.2227.
Stomata regulate gas exchange through the aerial plant epidermis by controlling the width of a pore bordered by two guard cells. Little is known about the genes that regulate stomatal development. We screened cotyledons from ethyl methanesulfonate-mutagenized seeds of Arabidopsis by light microscopy to identify mutants with altered stomatal morphology. Two mutants, designated too many mouths (tmm) and four lips (flp), were isolated with extra adjacent stomata. The tmm mutation results in stomatal clustering and increased precursor cell formation in cotyledons and a virtual absence of stomata in the inflorescence stem. The flp mutation results in many paired stomata and a small percentage of unpaired guard cells in cotyledons. The double mutant (tmm flp) exhibits aspects of both parental phenotypes. Both mutations appear to affect stomatal production more than patterning or differentiation. tmm regulates stomatal production by controlling the formation, and probably the activity, of the stomatal precursor cell.
气孔通过控制由两个保卫细胞围绕的孔隙宽度来调节植物地上部分表皮的气体交换。关于调控气孔发育的基因，人们了解甚少。我们通过光学显微镜筛选了经甲磺酸乙酯诱变的拟南芥种子的子叶，以鉴定气孔形态发生改变的突变体。分离出了两个突变体，分别命名为“口过多”（tmm）和“四唇”（flp），它们有额外相邻的气孔。tmm突变导致子叶中气孔聚集且前体细胞形成增加，而花序茎中几乎没有气孔。flp突变导致子叶中有许多成对的气孔以及一小部分不成对的保卫细胞。双突变体（tmm flp）表现出双亲表型的特征。这两种突变似乎对气孔产生的影响大于对其模式形成或分化的影响。tmm通过控制气孔前体细胞的形成以及可能的活性来调节气孔产生。
