Liu Zhuoyi, Yu Wenfei, Zhang Xiaowen, Huang Jinfeng, Wang Wei, Miao Miao, Hu Li, Wan Chao, Yuan Yuan, Wu Binghua, Lyu Meiling
College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
College of Horticulture, South China Agriculture University, Guangzhou 510642, China.
Plants (Basel). 2022 May 9;11(9):1269. doi: 10.3390/plants11091269.
Chitinase (EC 3.2.1.14) is a kind of chitin-degrading glycosidase, which plays important roles in the abiotic and biotic defense of plants. In this study, we conducted whole-genome annotation, molecular evolution, and gene expression analyses on the () gene family members of . Thirty-three () were identified from the latest Petunia genome database. According to the phylogenetic analyses, these genes were divided into GH18 and GH19 subgroups and further subdivided into five classes (Class I to Class V). Conserved motif arrangements indicated their functional relevance within each group. The expansion and homeology analyses showed that gene replication events played an important role in the evolution of and the increase of the GH18 subgroup members was the main reason for the expansion of the gene family in the evolution progress. By qRT-PCR analysis, we found that most of the showed a very low expression level in the normal growing plants. But lots of showed upregulated expression profiles when the plants suffered different abiotic stress conditions. Among them, five responded to high temperature and exhibited significantly upregulate expression level. Correspondingly, many hormone responses, as well as biotic and abiotic stress elements were found in the promoters of by using cis-acting element analysis. These results provide a foundation for the exploration of ' function and enrich the evolutionary process of the gene family.
几丁质酶（EC 3.2.1.14）是一种可降解几丁质的糖苷酶，在植物的非生物和生物防御中发挥着重要作用。在本研究中，我们对矮牵牛（Petunia）的（几丁质酶）基因家族成员进行了全基因组注释、分子进化和基因表达分析。从最新的矮牵牛基因组数据库中鉴定出了33个（几丁质酶）基因。根据系统发育分析，这些基因被分为GH18和GH19亚组，并进一步细分为五类（第一类至第五类）。保守基序排列表明了它们在每组中的功能相关性。基因复制事件的扩张和同源性分析表明，其在矮牵牛的进化中起重要作用，并且在进化过程中GH18亚组成员的增加是几丁质酶基因家族扩张的主要原因。通过qRT-PCR分析，我们发现大多数（几丁质酶基因）在正常生长的植物中表达水平非常低。但当植物遭受不同的非生物胁迫条件时，许多（几丁质酶基因）表现出上调的表达谱。其中，有五个（几丁质酶基因）对高温有响应，并表现出显著上调的表达水平。相应地，通过顺式作用元件分析在（几丁质酶基因）的启动子中发现了许多激素响应以及生物和非生物胁迫元件。这些结果为探索矮牵牛几丁质酶的功能提供了基础，并丰富了几丁质酶基因家族的进化过程。
