Jin P, Guo T, Becraft P W
Agronomy Department, Iowa State University, Ames, Iowa 50011, USA.
Genesis. 2000 Jul;27(3):104-16. doi: 10.1002/1526-968x(200007)27:3<104::aid-gene30>3.0.co;2-i.
The maize crinkly4 (cr4) gene encodes a predicted receptor kinase that is required for the normal differentiation of leaf epidermis (Becraft et al., 1996). Here we confirm that the presumptive cytoplasmic domain is capable of autophosphorylation on serine and threonine residues. The cr4 transcript is most abundant in young developing tissues of the shoot but was not detected in the root. Phenotypic analysis of strong mutant alleles indicates that cr4 functions throughout shoot development to control the differentiation of internal as well as epidermal tissues. However, epidermal cells appear most sensitive to perturbations in CR4 signaling because epidermal defects are more pronounced than internal cell defects. Epidermal cells show irregularities in shape, cell wall thickness and structure, cuticle formation, and vesicle trafficking. Some plants show tumor-like proliferations of cells on the leaves. Thus CR4 regulates an array of developmental responses including cell proliferation, fate, pattern, and differentiation suggesting a function analogous to growth factor responses in animals.
玉米皱缩4（cr4）基因编码一种预测的受体激酶，它是叶片表皮正常分化所必需的（Becraft等人，1996年）。在这里，我们证实了假定的细胞质结构域能够在丝氨酸和苏氨酸残基上进行自磷酸化。cr4转录本在茎尖幼嫩发育组织中最为丰富，但在根中未检测到。对强突变等位基因的表型分析表明，cr4在整个茎尖发育过程中发挥作用，以控制内部组织和表皮组织的分化。然而，表皮细胞似乎对CR4信号的扰动最为敏感，因为表皮缺陷比内部细胞缺陷更为明显。表皮细胞在形状、细胞壁厚度和结构、角质层形成以及囊泡运输方面表现出不规则性。一些植物的叶片上出现细胞的肿瘤样增殖。因此，CR4调节一系列发育反应，包括细胞增殖、命运、模式和分化，这表明其功能类似于动物中的生长因子反应。
