Abstract: Hexokinase (HXK) is a key enzyme in the glycolysis pathway,which is mainly involved in cellular signal transduction and glucose sensing. Studying the detailed characteristics and functions of HXK family genes of Pennisetum glaucum is helpful to further elucidate its regulatory role in the growth and development of this species. Studies on HXK gene family,most of the research materials in the past studies are dicotyledonous and monocotyledonous food crops,and few studies on abiotic stress. In this study,the hexokinase gene family of Pennisetum glaucum was analyzed basing on the whole genome data. A total of 12 PMhxk genes were identified and divided into 4 subgroups through phylogenetic analysis. Protein motif analysis showed that the PMhxk family had two conserved motif fragments,and cis-acting element analysis showed that there were a large number of stress response and plant hormone response elements in the promoter and enhancer regions of PMhxk genes. The expression analysis of PMhxk gene family showed that HXK gene of Pennisetum glaucum was mainly expressed in panicle tissue at heading stage,and some PMhxk members were significantly up-regulated under drought and salt stress,especially under drought stress. In conclusion,this study identified HXK gene family members in Pennisetum glaucum,and found significant tissue-specific and stress expression differences in this family members through comprehensive transcriptome data,which provided a reference for the study of hexokinase gene in grasses and valuable information for further exploration of the function of HXK gene family.

Key words: Pennisetum glaucum, Hexokinase, Gene Family, Drought and salt stress

摘要： 己糖激酶(Hexokinase,HXK)是糖酵解途径中的关键酶，在细胞信号传导和糖感知过程起重要作用。探究美洲狼尾草HXK家族基因的详细特征及功能，解析其在该物种生长发育各个环节中的调控作用，本研究基于美洲狼尾草全基因组数据对美洲狼尾草的己糖激酶基因家族展开分析，共鉴定出12个美洲狼尾草PMhxk基因，同时通过系统进化分析将其分为4个亚组。蛋白质基序分析表明PMhxk家族具有两个较为保守的motif片段，顺式作用元件分析表明PMhxk成员的启动子、增强子等调控区域有大量的胁迫响应与植物激素响应元件。PMhxk基因家族的表达分析表明，美洲狼尾草的HXK基因集中表达于抽穗期的穗组织中，部分PMhxk成员在干旱胁迫和盐胁迫中出现表达上调，且干旱胁迫更为明显。综上，本研究鉴定了美洲狼尾草HXK基因家族成员，并通过全面的转录组数据发现该家族成员具有显著的组织特异性和逆境表达差异性，为深入探讨HXK家族基因的功能提供了有价值的信息。

关键词: 美洲狼尾草, 己糖激酶, 基因家族, 干旱和盐胁迫