Characterization of temperature-sensitive mutants reveals a role for receptor-like kinase SCRAMBLED/STRUBBELIG in coordinating cell proliferation and differentiation during Arabidopsis leaf development
Characterization of temperature-sensitive mutants reveals a role for receptor-like kinase SCRAMBLED/STRUBBELIG in coordinating cell proliferation and differentiation during Arabidopsis leaf development
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温度敏感突变体的表征揭示了受体样激酶 SCRAMBLED/STRUBBELIG 在拟南芥叶片发育过程中协调细胞增殖和分化中的作用
DOI：
10.1111/j.1365-313x.2012.05109.x
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发表时间：
2012-12-01
期刊：
影响因子：
7.2
通讯作者：
He, Zu-Hua
中科院分区：
文献类型：
--
作者：
Lin, Lin;Zhong, Si-Hui;He, Zu-Hua
细胞增殖和细胞分化之间的平衡对叶片的构型至关重要。然而，确定协调叶片模式和细胞生长行为的因素是具有挑战性的。在这里，我们鉴定了一个具有叶片和脉序缺陷的温度敏感型拟南芥突变体。我们将该突变定位于scrbled/STRUBBELIG(SCM/SUB)受体样激酶基因的亚2等位基因，该基因在叶片发育中的功能尚未得到证实。该亚2突变体在高温(30℃)下表现出叶片发育受阻、叶片形状不对称和脉序改变，但在正常生长温度(22℃)下这些缺陷不那么明显。SCM/SUB功能的丧失会导致细胞增殖减少和细胞异常扩张，以及生长素模式的改变。SCM/SUB最初在整个叶原基中表达，后来局限于维管细胞，与其在早期叶片模式形成和脉序形成中的作用一致。此外，SCM/sub1基因的结构性表达还通过抑制细胞从增殖到扩增的转变来限制器官的生长。我们提出了SCM/亚介导的发育阶段特异的叶片模式信号的存在，并强调了细胞增殖和分化之间的平衡对叶片形态发生的重要性。
The balance between cell proliferation and cell differentiation is essential for leaf patterning. However, identification of the factors coordinating leaf patterning and cell growth behavior is challenging. Here, we characterized a temperature-sensitive Arabidopsis mutant with leaf blade and venation defects. We mapped the mutation to the sub-2 allele of the SCRAMBLED/STRUBBELIG (SCM/SUB) receptor-like kinase gene whose functions in leaf development have not been demonstrated. The sub-2 mutant displayed impaired blade development, asymmetric leaf shape and altered venation patterning under high ambient temperature (30 degrees C), but these defects were less pronounced at normal growth temperature (22 degrees C). Loss of SCM/SUB function results in reduced cell proliferation and abnormal cell expansion, as well as altered auxin patterning. SCM/SUB is initially expressed throughout leaf primordia and becomes restricted to the vascular cells, coinciding with its roles in early leaf patterning and venation formation. Furthermore, constitutive expression of the SCM/SUB gene also restricts organ growth by inhibiting the transition from cell proliferation to expansion. We propose the existence of a SCM/SUB-mediated developmental stage-specific signal for leaf patterning, and highlight the importance of the balance between cell proliferation and differentiation for leaf morphogenesis.