de Oliveira Luiz Felipe Valter, Christoff Ana Paula, de Lima Júlio Cesar, de Ross Bruno Comparsi Feijó, Sachetto-Martins Gilberto, Margis-Pinheiro Marcia, Margis Rogerio
Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul, Brazil; Centro de Biotecnologia e Programa de Pós-Graduação em Biologia Celular e Molecular, Universidade Federal do Rio Grande do Sul, Brazil.
Centro de Biotecnologia e Programa de Pós-Graduação em Biologia Celular e Molecular, Universidade Federal do Rio Grande do Sul, Brazil.
Plant Sci. 2014 Dec;229:181-192. doi: 10.1016/j.plantsci.2014.09.007. Epub 2014 Sep 22.
The environment is a dynamic system in which life forms adapt. Wall-Associated Kinases (WAK) are a subfamily of receptor-like kinases associated with the cell wall. These genes have been suggested as sensors of the extracellular environment and triggers of intracellular signals. They belong to the ePK superfamily with or without a conserved arginine before the catalytic subdomain VIB, which characterizes RD and non-RD WAKs. WAK is a large subfamily in rice. We performed an extensive comparison of WAK genes from A. thaliana (AtWAK), O. sativa japonica and indica subspecies (OsWAK). Phylogenetic studies and WAK domain characterization allowed for the identification of two distinct groups of WAK genes in Arabidopsis and rice. One group corresponds to a cluster containing only OsWAKs that most likely expanded after the monocot-dicot separation, which evolved into a non-RD kinase class. The other group comprises classical RD-kinases with both AtWAK and OsWAK representatives. Clusterization analysis using extracellular and kinase domains demonstrated putative functional redundancy for some genes, but also highlighted genes that could recognize similar extracellular stimuli and activate different cascades. The gene expression pattern of WAKs in response to cold suggests differences in the regulation of the OsWAK genes in the indica and japonica subspecies. Our results also confirm the hypothesis of functional diversification between A. thaliana and O. sativa WAK genes. Furthermore, we propose that plant WAKs constitute two evolutionarily related but independent subfamilies: WAK-RD and WAK-nonRD. Recognition of this structural division will further provide insights to understanding WAK functions and regulations.
环境是一个生命形式能在其中适应的动态系统。壁相关激酶（WAK）是一类与细胞壁相关的类受体激酶亚家族。这些基因被认为是细胞外环境的传感器和细胞内信号的触发因子。它们属于ePK超家族，在催化亚结构域VIB之前有或没有保守的精氨酸，这是区分RD型和非RD型WAK的特征。WAK是水稻中的一个大亚家族。我们对拟南芥（AtWAK）、粳稻和籼稻亚种（OsWAK）的WAK基因进行了广泛比较。系统发育研究和WAK结构域特征分析使得在拟南芥和水稻中鉴定出了两组不同的WAK基因。一组对应于一个仅包含OsWAK的簇，该簇很可能在单子叶植物与双子叶植物分离后发生了扩张，进化成了一个非RD激酶类。另一组包括具有AtWAK和OsWAK代表的经典RD激酶。使用细胞外结构域和激酶结构域的聚类分析表明一些基因存在假定的功能冗余，但也突出了那些可能识别相似细胞外刺激并激活不同级联反应的基因。WAK对寒冷响应的基因表达模式表明籼稻和粳稻亚种中OsWAK基因的调控存在差异。我们的结果也证实了拟南芥和水稻WAK基因之间功能多样化的假设。此外，我们提出植物WAK构成了两个进化相关但独立的亚家族：WAK-RD和WAK-nonRD。认识到这种结构划分将进一步为理解WAK的功能和调控提供见解。
