College of Agriculture, Ludong University, Yantai, Shandong 264025, PR China; MOA Key Laboratory of Horticultural Crop Biology and Germplasm Innovation, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, PR China.
Plant Physiol Biochem. 2013 Oct;71:11-21. doi: 10.1016/j.plaphy.2013.06.022. Epub 2013 Jul 4.
NAC (NAM, ATAF1,2, and CUC2) proteins constitute one of the largest families of plant-specific transcription factors. To date, little is known about the NAC genes in the apple (Malus domestica). In this study, a total of 180 NAC genes were identified in the apple genome and were phylogenetically clustered into six groups (I-VI) with the NAC genes from Arabidopsis and rice. The predicted apple NAC genes were distributed across all of 17 chromosomes at various densities. Additionally, the gene structure and motif compositions of the apple NAC genes were analyzed. Moreover, the expression of 29 selected apple NAC genes was analyzed in different tissues and under different abiotic stress conditions. All of the selected genes, with the exception of four genes, were expressed in at least one of the tissues tested, which indicates that the NAC genes are involved in various aspects of the physiological and developmental processes of the apple. Encouragingly, 17 of the selected genes were found to respond to one or more of the abiotic stress treatments, and these 17 genes included not only the expected 7 genes that were clustered with the well-known stress-related marker genes in group IV but also 10 genes located in other subgroups, none of which contains members that have been reported to be stress-related. To the best of our knowledge, this report describes the first genome-wide analysis of the apple NAC gene family, and the results should provide valuable information for understanding the classification and putative functions of this family.
NAC（NAM、ATAF1、2 和 CUC2）蛋白构成了植物特异性转录因子家族中最大的家族之一。迄今为止，人们对苹果（Malus domestica）中的 NAC 基因知之甚少。在这项研究中，在苹果基因组中鉴定出了总共 180 个 NAC 基因，并与拟南芥和水稻的 NAC 基因一起系统发育聚类为六个组（I-VI）。预测的苹果 NAC 基因分布在 17 条染色体的各个位置，密度各不相同。此外，还分析了苹果 NAC 基因的基因结构和基序组成。此外，还分析了 29 个选定的苹果 NAC 基因在不同组织和不同非生物胁迫条件下的表达。除了四个基因外，所有选定的基因都在至少一种测试组织中表达，这表明 NAC 基因参与了苹果生理和发育过程的各个方面。令人鼓舞的是，在选定的 17 个基因中，有 17 个基因对一种或多种非生物胁迫处理有反应，这 17 个基因不仅包括与第四组中众所周知的与应激相关的标记基因聚类的预期 7 个基因，还包括 10 个位于其他亚组中的基因，其中没有一个包含被报道与应激相关的成员。据我们所知，本报告首次对苹果 NAC 基因家族进行了全基因组分析，结果应为理解该家族的分类和可能的功能提供有价值的信息。
