Smertenko Andrei, Clare Shaun J, Effertz Karl, Parish Alyssa, Ross Austin, Schmidt Sharol
Plant Molecular Sciences Graduate Program, Washington State University, Pullman, WA, USA.
Institute of Biological Chemistry, Washington State University, Pullman, WA, USA.
J Exp Bot. 2021 Feb 24;72(4):1034-1045. doi: 10.1093/jxb/eraa513.
TPX2 proteins were first identified in vertebrates as a key mitotic spindle assembly factor. Subsequent studies demonstrated that TPX2 is an intricate protein, with functionally and structurally distinct domains and motifs including Aurora kinase-binding, importin-binding, central microtubule-binding, and C-terminal TPX2 conserved domain, among others. The first plant TPX2-like protein, WAVE-DAMPENED2, was identified in Arabidopsis as a dominant mutation responsible for reducing the waviness of roots grown on slanted agar plates. Each plant genome encodes at least one 'canonical' protein with all TPX2 domains and a family of proteins (20 in Arabidopsis) that diversified to contain only some of the domains. Although all plant TPX2-family proteins to date bind microtubules, they function in distinct processes such as cell division, regulation of hypocotyl cell elongation by hormones and light signals, vascular development, or abiotic stress tolerance. Consequently, their expression patterns, regulation, and functions have diverged considerably. Here we summarize the current body of knowledge surrounding plant TPX2-family proteins.
TPX2蛋白最初在脊椎动物中被鉴定为一种关键的有丝分裂纺锤体组装因子。随后的研究表明，TPX2是一种复杂的蛋白质，具有功能和结构上不同的结构域和基序，包括极光激酶结合、输入蛋白结合、中央微管结合和C端TPX2保守结构域等。第一个植物类TPX2蛋白WAVE-DAMPENED2在拟南芥中被鉴定为一种显性突变，该突变导致在倾斜琼脂平板上生长的根的波纹度降低。每个植物基因组编码至少一种具有所有TPX2结构域的“典型”蛋白和一个蛋白家族（拟南芥中有20种），这些蛋白经过多样化进化，只包含部分结构域。尽管迄今为止所有植物TPX2家族蛋白都能结合微管，但它们在不同的过程中发挥作用，如细胞分裂、激素和光信号对下胚轴细胞伸长的调节、维管发育或非生物胁迫耐受性。因此，它们的表达模式、调控和功能有很大差异。在这里，我们总结了目前关于植物TPX2家族蛋白的知识体系。
