Chan R L, Gago G M, Palena C M, Gonzalez D H
Area Biología Molecular, Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR) and Programa Multidisciplinario de Biología Experimental (PROMUBIE, CONICET), Suipacha 531, 2000 Rosario, Argentina.
Biochim Biophys Acta. 1998 Oct 23;1442(1):1-19. doi: 10.1016/s0167-4781(98)00119-5.
The homeobox is a 180 bp consensus DNA sequence present in a number of genes involved in developmental processes. This review focuses on the structure and function of plant homeobox genes and of the proteins they encode. Plant homeobox genes have been identified in studies using mutants, degenerate oligonucleotides deduced from conserved sequences, differential screening or binding to known promoters. According to sequence conservation, plant homeoboxes can be subdivided into different families, each comprising several members. Evolutionary studies indicate that the different families have diverged prior to the separation of the branches leading to animals, plants and fungi. Accordingly, members of different families show characteristic structural and functional properties. As an example, kn1-like genes seem to be involved in different aspects of the control of cell fate determination in the shoot meristem; HD-Zip genes, which encode proteins containing a leucine zipper motif adjacent to the homeodomain, are believed to operate at later stages of development; and gl2-like genes are involved in epidermal cell differentiation. Future studies should be oriented to discern the precise function of the many homeobox genes present in plant genomes, and to evaluate their use as modifiers of plant development.
同源异型框是一段180个碱基对的共有DNA序列，存在于许多参与发育过程的基因中。本综述聚焦于植物同源异型框基因及其编码蛋白的结构与功能。植物同源异型框基因已在多项研究中被鉴定出来，这些研究采用了突变体、从保守序列推导而来的简并寡核苷酸、差异筛选或与已知启动子结合等方法。根据序列保守性，植物同源异型框可细分为不同家族，每个家族包含多个成员。进化研究表明，不同家族在导致动物、植物和真菌的分支分离之前就已分化。因此，不同家族的成员具有独特的结构和功能特性。例如，kn1样基因似乎参与了茎尖分生组织中细胞命运决定控制的不同方面；HD-Zip基因编码的蛋白在同源异型结构域附近含有亮氨酸拉链基序，被认为在发育后期发挥作用；而gl2样基因则参与表皮细胞分化。未来的研究应致力于明确植物基因组中众多同源异型框基因的确切功能，并评估它们作为植物发育修饰因子的用途。
