王秀美 倪珊珊 李乾玉 李小芳 林争春 陈裕坤 林玉玲 赖钟雄 杜迎刚

摘  要：磷脂酶C（phospholipase C，PLC）广泛参与植物的生命活动和代谢过程，在抵御真菌感染的过程中发挥重要作用。本研究基于非洲菊转录组测序数据，鉴定出13个非洲菊PLC基因家族成员，其中NPC有3个，PI-PLC有10个。非洲菊PLC的蛋白序列长度在98～594 aa之间，蛋白理论分子量为11 410.25～67 998.85 kDa，等电点为4.74～9.59，均为不稳定亲水蛋白。亚细胞定位预测结果显示，13个成员分别定位于细胞壁、细胞膜、细胞质、叶绿体和细胞核中，表明不同成员功能上可能存在多样性。进化树分析表明，13个非洲菊PLC蛋白可分为2个亚组，进化关系较近的蛋白结构组成相似。非洲菊PLC家族成员在拟南芥中的同源蛋白PLC2、PLC4、AT2G40116可相互作用。非洲菊转录组的FPKM值分析表明，GjPLC2、GjPLC3、GjPLC8、GjPLC10在非洲菊中表达量高，感病植株中变化大，可能在抵御真菌感染过程中发挥重要作用。研究结果可为进一步研究非洲菊PLC基因的生物学功能提供依据。

关键词：非洲菊;磷脂酶C;基因家族;进化分析

中图分类号：S682.1      文献标识码：A

Abstract： Phospholipase C （PLC） is widely involved in the life activities and metabolism processes of plants， and plays an important role in the process of resisting fungal infection. Based on the results of the transcriptome sequencing in Gerbera jamesonii， 13 members of G. jamesonii PLC gene family， including 3 NPC and 10 PI-PLC were identified in the study. The sequences of G. jamesonii PLC proteins ranged from 98 to 594 aa in length， theoretical molecular weight varied from 11 410.25 to 67 998.85 kDa， isoelectric point in the range of 4.74 to 9.59， and all were unstable hydrophilic proteins. The prediction results of subcellular localization showed that the 13 members were located in the cell wall， cell membrane， cytoplasm， chloroplast and nucleus， indicating that there might be diversity in functions of different mem-bers. Evolutionary trees analysis showed that 13 PLC proteins of G. jamesonii were divided into two subgroups， the structure and composition of proteins with relatively close evolutionary relationship were similar. G. jamesoniis homo-logous protein PLC2， PLC4 and AT2G40116 in Arabidopsis thaliana can interact with each other. The FPKM value analysis of G. jamesonii transcription showed that GjPLC2， GjPLC3， GjPLC8 and GjPLC10 were highly expressed in G. jamesonii and changed greatly in infected plants， which may play an important role in preventing fungal infection. These results could provide the basis for further study of the biological function of G. jamesonii PLC genes.

Keywords： Gerbera jamesonii Bolus; Phospholipase C; gene family; evolutionary analysis

DOI： 10.3969/j.issn.1000-2561.2021.05.010

磷脂酶C（phospholipase C，PLC）是一種普遍存在于动物、植物和微生物细胞中的脂质水解酶，根据作用底物的不同可主要分为磷脂酰肌醇特异性磷脂酶C（phosphoinositide-specific PLC，PI-PLC）和非特异性磷脂酶C（non-specific PLC，NPC）[1-2]。PI-PLC蛋白由N端的EF手型结构域、C端的C2结构域及中间的X、Y结构域组成[2]，主要水解磷脂酰肌醇4，5-二磷酸（phosphatidyfinositol4， 5-bisphosphate，PIP2），生成水溶性三磷酸肌醇（inositol 1，4，5-trisphosphate，IP3）和脂溶性二酰甘油（diacylglycerol，DAG）[3]。而NPC蛋白只包含一个具有磷脂酶活性的磷酸酯酶区，主要水解磷脂酰乙醇胺（phosphatidylethanolamine，PE）、磷脂酰胆碱（phosphatidylcholine，PC）和磷脂酰甘油（phosphatidylglycerol，PG），生成DAG和相应磷酸盐[4]。……