In higher plants, the light-harvesting chlorophyll a/b-binding (Lhc) proteins function in multiple processes that are critical to plant growth, development, and abiotic stress response. However, the Lhc gene family has not been well characterized in the important fruit crop, apple (Malus × domestica Borkh.). In this study, we identified 27 Lhc genes in the apple genome. Phylogenetic analysis showed that the Lhc gene family could be classified into three major subfamilies, each of whose members shared similar conserved motifs. Evolutionary analysis indicated that duplicated MdLhc genes were primarily under purifying selection. MdLhcs were expressed at varying levels in all tissues examined and showed different expression patterns under drought stress. The overexpression of MdLhcb4.3 in transgenic Arabidopsis and apple callus enhanced their tolerance to drought and osmotic stress. Taken together, these results demonstrate the important role of Lhc proteins in the regulation of plant resistance to drought and osmotic stress and provide valuable information for further study of Lhc functions in apple.

在高等植物中，光捕获叶绿素a / b结合（Lhc）蛋白在多个过程中起作用，这些过程对于植物的生长，发育和非生物胁迫响应至关重要。然而，Lhc基因家族在重要的水果作物苹果（苹果（Malus  ×  domestica Borkh。））中尚未得到很好的表征。在这项研究中，我们确定了苹果基因组中的27个Lhc基因。系统发育分析表明，Lhc基因家族可以分为三个主要的亚家族，每个亚家族具有相似的保守基序。进化分析表明，重复的MdLhc基因主要在纯化选择中。MdLhc在所有受检组织中均以不同水平表达，在干旱胁迫下表现出不同的表达方式。MdLhcb4.3在转基因拟南芥和苹果愈伤组织中的过表达增强了它们对干旱和渗透胁迫的耐受性。综上所述，这些结果证明了Lhc蛋白在调节植物对干旱和渗透胁迫的抗性中的重要作用，并为进一步研究苹果中Lhc功能提供了有价值的信息。