文献类型：期刊文献

英文题名：Evolution and Function of the Populus SABATH Family Reveal That a Single Amino Acid Change Results in a Substrate Switch

作者：Han, Xue-Min[1] Yang, Qi[2] Liu, Yan-Jing[3] Yang, Zhi-Ling[1] Wang, Xiao-Ru[1] Zeng, Qing-Yin[2] Yang, Hai-Ling[1]

第一作者：Han, Xue-Min

通信作者：Yang, HL[1]

机构：[1]Beijing Forestry Univ, Coll Biol Sci & Biotechnol, Beijing 100083, Peoples R China;[2]Chinese Acad Sci, Inst Bot, State Key Lab Systemat & Evolutionary Bot, Beijing 100093, Peoples R China;[3]Chinese Acad Forestry, State Key Lab Tree Genet & Breeding, Beijing 100091, Peoples R China

年份：2018

卷号：59

期号：2

起止页码：392-403

外文期刊名：PLANT AND CELL PHYSIOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000425507200015)】；

基金：This study was supported by grants from the National Natural Science Foundation of China [NSFC 31570664 and 31425006].

语种：英文

外文关键词：Enzyme activity; Enzyme family; Expression divergence; Molecular evolution; Populus trichocarpa; Substrate switch

摘要：Evolutionary mechanisms of substrate specificities of enzyme families remain poorly understood. Plant SABATH methyltransferases catalyze methylation of the carboxyl group of various low molecular weight metabolites. Investigation of the functional diversification of the SABATH family in plants could shed light on the evolution of substrate specificities in this enzyme family. Previous studies identified 28 SABATH genes from the Populus trichocarpa genome. In this study, we re-annotated the Populus SABATH gene family, and performed molecular evolution, gene expression and biochemical analyses of this large gene family. Twenty-eight Populus SABATH genes were divided into three classes with distinct divergences in their gene structure, expression responses to abiotic stressors and enzymatic properties of encoded proteins. Populus class I SABATH proteins converted IAA to methyl-IAA, class II SABATH proteins converted benzoic acid (BA) and salicylic acid (SA) to methyl-BA and methyl-SA, while class III SABATH proteins converted farnesoic acid (FA) to methyl-FA. For Populus class II SABATH proteins, both forward and reverse mutagenesis studies showed that a single amino acid switch between PtSABATH4 and PtSABATH24 resulted in substrate switch. Our findings provide new insights into the evolution of substrate specificities of enzyme families.