Zhang Zhongrong, Zhu Ranran, Ji Xuehua, Li Hui Ji, Lv Hui, Zhang Hai Ying
College of Agriculture, Shihezi University, Xinjiang Production and Construction Corps Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization, Shihezi, Xinjiang 832000, China.
Int J Genomics. 2021 Jan 25;2021:8105124. doi: 10.1155/2021/8105124. eCollection 2021.
HD-ZIP is a unique type of transcription factor in plants, which are closely linked to the regulation of plant growth and development, the response to abiotic stress, and disease resistance. However, there is little known about the HD-ZIP gene family of pepper. In this study, 40 HD-ZIP family members were analyzed in the pepper genome. The analysis indicated that the introns number of Ca-HD-ZIP varied from 1 to 17; the number of amino acids was between 119 and 841; the theoretical isoelectric point was between 4.54 and 9.85; the molecular weight was between 14.04 and 92.56; most of them were unstable proteins. The phylogenetic tree divided into 4 subfamilies; 40 genes were located on different chromosomes, and all of them contained the motif 1; two pairs of parallel genes of six paralogism genes were fragment duplications which occurred in 58.28~88.24 million years ago. There were multiple pressure-related action elements upstream of the start codon of the family. Protein interaction network proved to be coexpression phenomenon between () and (, ), and three regions of them were highly homology. The expression level of gene was different with tissues and developmental stages, which suggested that CaHD-ZIP may be involved in biological functions during pepper progress. In addition, Pepper HD-ZIP I and II genes played a major role in salt stress. , , , , , and were significantly induced in response to salt stress. Notably, the expression of , , , and , homologs of Arabidopsis and genes, was significantly upregulated by salt stresses. possesses two closely linked ABA action elements, and its expression level increased significantly at 4 h under salt stress. qRT-P-CR and transcription analysis showed that the expression of and CaHDZ10 was upregulated under short-term salt stress, but was downregulated with long-term salt stress, which provided a theoretical basis for research the function of in response to abiotic stress.
HD-ZIP是植物中一种独特的转录因子类型，与植物生长发育的调控、对非生物胁迫的响应以及抗病性密切相关。然而，关于辣椒的HD-ZIP基因家族知之甚少。在本研究中，对辣椒基因组中的40个HD-ZIP家族成员进行了分析。分析表明，Ca-HD-ZIP的内含子数量从1到17不等；氨基酸数量在119到841之间；理论等电点在4.54到9.85之间；分子量在14.04到92.56之间；它们中的大多数是不稳定蛋白。系统发育树分为4个亚家族；40个基因位于不同染色体上，且都含有基序1；6个旁系同源基因中的两对平行基因是片段重复，发生在5828万至8824万年前。该家族起始密码子上游存在多个与胁迫相关的作用元件。蛋白质相互作用网络证明（）与（，）之间存在共表达现象，且它们的三个区域具有高度同源性。基因的表达水平随组织和发育阶段而不同，这表明CaHD-ZIP可能参与辣椒生长过程中的生物学功能。此外，辣椒HD-ZIP I和II基因在盐胁迫中起主要作用。，，，，，和在盐胁迫响应中显著诱导。值得注意的是，拟南芥和基因的同源物，，，和的表达在盐胁迫下显著上调。拥有两个紧密相连的ABA作用元件，其表达水平在盐胁迫下4小时显著增加。qRT-P-CR和转录分析表明，在短期盐胁迫下和CaHDZ10的表达上调，但在长期盐胁迫下下调，这为研究在非生物胁迫响应中的功能提供了理论依据。
