植物液泡加工酶研究进展

doi:10.13560/j.cnki.biotech.bull.1985.2020-1131

摘要/Abstract

摘要：

植物液泡加工酶(vacuolar processing enzyme,VPE)是一种天冬氨酸特异性的半胱氨酸蛋白酶,属于Peptidase C13家族,对于天冬氨酸和天冬酰胺残基的羧基肽链有底物专一性。VPE无论是在结构上还是功能上都与动物的caspase-1蛋白具有相似性,VPE是植物中负责液泡蛋白成熟和活化的蛋白酶,在不同的植物器官与植物发育和死亡的不同阶段发挥多功能作用,通过引发液泡破裂和启动蛋白水解级联介导程序性细胞死亡(programmed cell death,PCD)。VPE还具有肽连接活性,它负责在某些植物中产生环肽。被子植物的VPE在进化过程中出现了4种类型:α型VPE、β型VPE、γ型VPE和δ型VPE。总结了植物VPE的进化与分类、成熟和活化过程、VPE的功能,以及该领域的最新进展和未来的研究领域,以便更全面地了解VPE在植物中的作用。

关键词: 液泡加工酶, 程序性细胞死亡, 半胱氨酸蛋白酶, 生长发育

Abstract:

Plant vacuolar processing enzyme(VPE)is an aspartic acid specific cysteine protease. VPE belongs to the peptidase C13 family and has substrate specificity for the carboxyl peptide chain of aspartic acid and asparagine residues. VPE is similar to caspase-1 protein from animal in both structure and function. VPE is a protease responsible for maturation and activation of vacuolar proteins in plants. It plays a multifunctional role in different plant organs and different stages of plant development and death,and mediates programmed cell death(PCD)by triggering vacuole rupture and initiating the proteolytic cascade. VPE also has peptide linking activity,which is responsible for the production of cyclic peptides in certain plants. There are four types of VPE in angiosperms during the evolution process:alpha-type VPE,beta-type VPE,gamma-type VPE,and delta-type VPE. This article summarizes the evolution,classification,maturation,activation processes and the functions of VPE in plant,as well as the latest progress and future research areas in this field,aiming to more comprehensively understand the role of VPE in plants.

Key words: vacuolar processing enzyme, programmed cell death, cysteine protease, growth and development

苏雨, 李宗芸, 韩永华. 植物液泡加工酶研究进展[J]. 生物技术通报, 2021, 37(6): 181-191.

SU Yu, LI Zong-yun, HAN Yong-hua. Advances in Plant Vacuolar Processing Enzymes[J]. Biotechnology Bulletin, 2021, 37(6): 181-191.

图/表 4

图1 VPE的主要三维结构蓝色表示N端信号肽,黄色表示可切割的前肽,橙色表示C端信号肽即LASM结构域,灰色表示成熟蛋白。参照Barend等[8]修改

Fig. 1 Main three-dimensional structure of VPE Blue represents N-terminal signal peptide,yellow represents cleavable prepeptide,orange represents C-terminal prepeptide,i.e. LSAM domain,and gray represents mature protein. Refer to Barend et al[8]

表1 VPE在植物PCD及相关过程中的作用

Table 1 VPE functions in plant PCD and the related processes

物种 Species	组织 Organization	VPE在不同类型PCD中的研究 Study on VPE in different types of PCD	参考文献 References
烟草	叶	液泡膜裂解介导的PCD,沉默VPE及caspase-1抑制剂能够抑制PCD及病毒增殖	[9,34-35]
	叶	VPE沉默诱导气孔关闭,抑制PCD	[36]
	花瓣	VPE基因表达的上调	[37]
	悬浮培养细胞	液泡膜裂解介导的PCD,VPE缺失及caspase-1抑制剂对PCD的抑制,VPE基因上调与VPE活性增加	[38-39]
	根	Ced-9抑制铝诱导的PCD促进植物对铝的耐受	[40]
拟南芥	花药	γ VPE基因表达的上调	[41]
	叶	液泡膜裂解介导的PCD,VPE缺失突变体及caspase-1抑制剂对PCD的抑制作用,重组p35蛋白对VPE活性的抑制作用	[42-43]
	叶	VPE缺失突变体的卵子产孢量减少,卵子感染期间γ VPE活性的增加	[44]
	叶、侧根、悬浮培养细胞	α VPE和γ VPE基因的上调	[45-46]
	叶原生质体	caspase-1抑制剂和p35超表达对PCD的抑制作用	[47]
	种皮	δ VPE突变体内珠被两层细胞PCD延迟	[48]
水稻	胚珠	VPE基因随类caspase活性的增加上调	[49]
水稻	种子	caspase-1抑制剂对PCD的抑制使VPE活性提高	[44]
土豆	块茎顶芽分生组织	caspase-1抑制剂抑制PCD使VPE活性提高	[50]
苹果	叶	VPE基因的表达在HR过程中上调	[51]
番茄	叶	Bcl-2过表达下调VPE基因表达,在抑制NaCl诱导的PCD过程中起重要作用	[52-53]
番茄	悬浮培养细胞	caspase-1抑制剂对PCD的抑制作用	[54]
大豆	叶原生质体	VPE基因上调,鉴定两种VPE基因表达转录因子	[55]
甘薯	叶、根	参与发育、衰老、生殖过程中的PCD	[56]

图2 液泡介导细胞死亡的两种不同途径 a:非破坏性途径;b:破坏性途径;v:液泡;cw:细胞膜;vm:液泡膜。参照Hara Nishimura等[60]修改

Fig. 2 Two different ways of vacuole-mediated cell death a represents the non-destructive way,b represents the non-destructive way,v represents vacuole,cw represents cell membrane,and vm represents vacuole membrane. Refer to Hara Nishimura et al[60]

图3 植物液泡加工酶系统进化树该分析涉及116个不同物种的氨基酸序列。按比例绘制,分枝长度与用来推断系统发育树的进化距离的单位相同。进化距离采用Poisson校正法计算,以每个位点的氨基酸取代数为单位。参照Kenji等[80]修改

Fig. 3 Phylogenetic tree of vacuolase system in plants The analysis is involved 116 amino acid sequences. The tree is drawn to scale,with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. The evolutionary distances were computed using the Poisson correction method and are in the units of the number of amino acid substitutions per site. Refer to Kenji et al[80]

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