大肠杆菌核糖核酸酶调控机制研究

doi:10.13560/j.cnki.biotech.bull.1985.2021-0341

摘要/Abstract

摘要：

核糖核酸酶参与体内多种RNA代谢反应,对细菌生理功能调节起重要作用。细菌需要进化出多种策略来对体内核糖核酸酶进行调节,以避免对RNA进行不必要地降解。目前对大肠杆菌核糖核酸酶调节机制的研究包括转录后调控、翻译后修饰、细胞定位及相关抑制剂等。本文系统性地阐述了大肠杆菌核糖核酸酶的分类、功能及其体内调控机制,总结了不同环境压力下大肠杆菌对自身核糖核酸酶进行适应性调节的响应机制及存在的问题。

关键词: 大肠杆菌, 核糖核酸酶, 调控机制, RNA代谢, 细菌应激

Abstract:

Ribonucleases（RNases）involve in almost every aspect of RNA metabolism,and play important regulating role in the physiological functions of bacteria. Bacteria have evolved multiple strategies to regulate RNases to avoid unnecessary RNA degradation. To date,the regulation mechanisms include post-transcriptional regulation,post-translational modification,cellular localization and related trans-acting inhibitors. Here,we systematically describe and explain the classification,function and regulation mechanism of the RNases in E. coli,and summarize the response mechanism of E. coli adaptive regulation to its RNases under different environmental pressures as well as existing issues.

Key words: Escherichia coli, ribonuclease（RNase）, regulation mechanism, RNA metabolism, bacterial stress response

孙曼銮, 葛赛, 卜佳, 朱壮彦. 大肠杆菌核糖核酸酶调控机制研究[J]. 生物技术通报, 2022, 38(3): 234-245.

SUN Man-luan, GE Sai, BU Jia, ZHU Zhuang-yan. Regulation Mechanism of Ribonucleases in Escherichia coli[J]. Biotechnology Bulletin, 2022, 38(3): 234-245.

图/表 6

参考文献 83

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名称 Name		编码基因 Gene	酶活特异性 Enzyme activity	主要生理功能 Physiological functions	已知主要调控方式 Regulation known	主要参考文献 Reference
核糖核酸内切酶	RNAse I	rna	内切酶活性,Ca²⁺依赖的双链mRNA活性	尚不明确	可能与周质空间及胞内定位调节有关	[8-9]
	RNAse III	rnc	双链特异性内切酶活性	rRNA的成熟	转录后自我调控;酶蛋白磷酸化修饰;反式作用因子调控	[10-13]
	RNase BN	rbn	内切酶/外切酶活性	sRNA的降解,mRNA降解	自身mRNA稳定性调节	[14-15]
	RNase E	rne	内切酶活性	mRNA的降解;rRNA及tRNA的成熟	转录后自我调控;酶蛋白磷酸化修饰;反式作用因子调控;sRNA;小分子结合及胞内定位	[16-21]
	RNase P	rnpA/rnpB	内切酶活性	5' tRNA的成熟	未知	[22]
	RNase G	rng	内切酶活性	rRNA的成熟	未知	[23]
	RNase H家族	rnhA/rnhB	RNA/DNA杂交体中RNA的切割与修饰	参与DNA复制过程中RNA的调整	未知	[24]
	YbeY	ybeY	内切酶活性	rRNA成熟与质控,16S rRNA3'末端的加工	未知	[25]
	RNase LS	rnlA/rnlB	内切酶活性	降解T4噬菌体编码的mRNA	未知	[26]
核糖核酸外切酶	PNPase	pnp	磷酸盐依赖的3'-5'外切酶活性	mRNA的降解;rRNA及tRNA的成熟;sRNAs调控伴侣	自我调控;反式作用因子调控;sRNA的调控	[27-30]
	RNAse II	rnb	3'-5'外切酶活性	mRNA的降解;rRNA及tRNA的成熟	酶蛋白的乙酰化修饰	[31-33]
	RNase R	rnr	3'-5'外切酶活性	mRNA的降解;rRNA的成熟与质控;tRNA的成熟	酶蛋白的乙酰化修饰	[13,34-35]
	RNase PH	rph	磷酸盐依赖的3'-5'外切酶活性	tRNA与rRNA的成熟;rRNA的降解	蛋白稳定性调节;RNase II调节（待发表资料）	[36-37]
	RNase T	rnt	3'-5'外切酶活性	tRNA与rRNA的成熟	未知	[38]
	RNase D	rnd	3'-5'外切酶活性	tRNA的成熟	未知	[22]
	Oligo RNase	orn	3'-5'外切酶活性	短链核苷酸的去除	未知	[2]
	RNase AM	trpH/yciV	5'-3'外切酶活性	5S、23S 及16S rRNA的5'末端成熟	未知	[39]

名称 Name		编码基因 Gene	酶活特异性 Enzyme activity	主要生理功能 Physiological functions	已知主要调控方式 Regulation known	主要参考文献 Reference
核糖核酸内切酶	RNAse I	rna	内切酶活性,Ca²⁺依赖的双链mRNA活性	尚不明确	可能与周质空间及胞内定位调节有关	[8-9]
	RNAse III	rnc	双链特异性内切酶活性	rRNA的成熟	转录后自我调控;酶蛋白磷酸化修饰;反式作用因子调控	[10-13]
	RNase BN	rbn	内切酶/外切酶活性	sRNA的降解,mRNA降解	自身mRNA稳定性调节	[14-15]
	RNase E	rne	内切酶活性	mRNA的降解;rRNA及tRNA的成熟	转录后自我调控;酶蛋白磷酸化修饰;反式作用因子调控;sRNA;小分子结合及胞内定位	[16-21]
	RNase P	rnpA/rnpB	内切酶活性	5' tRNA的成熟	未知	[22]
	RNase G	rng	内切酶活性	rRNA的成熟	未知	[23]
	RNase H家族	rnhA/rnhB	RNA/DNA杂交体中RNA的切割与修饰	参与DNA复制过程中RNA的调整	未知	[24]
	YbeY	ybeY	内切酶活性	rRNA成熟与质控,16S rRNA3'末端的加工	未知	[25]
	RNase LS	rnlA/rnlB	内切酶活性	降解T4噬菌体编码的mRNA	未知	[26]
核糖核酸外切酶	PNPase	pnp	磷酸盐依赖的3'-5'外切酶活性	mRNA的降解;rRNA及tRNA的成熟;sRNAs调控伴侣	自我调控;反式作用因子调控;sRNA的调控	[27-30]
	RNAse II	rnb	3'-5'外切酶活性	mRNA的降解;rRNA及tRNA的成熟	酶蛋白的乙酰化修饰	[31-33]
	RNase R	rnr	3'-5'外切酶活性	mRNA的降解;rRNA的成熟与质控;tRNA的成熟	酶蛋白的乙酰化修饰	[13,34-35]
	RNase PH	rph	磷酸盐依赖的3'-5'外切酶活性	tRNA与rRNA的成熟;rRNA的降解	蛋白稳定性调节;RNase II调节（待发表资料）	[36-37]
	RNase T	rnt	3'-5'外切酶活性	tRNA与rRNA的成熟	未知	[38]
	RNase D	rnd	3'-5'外切酶活性	tRNA的成熟	未知	[22]
	Oligo RNase	orn	3'-5'外切酶活性	短链核苷酸的去除	未知	[2]
	RNase AM	trpH/yciV	5'-3'外切酶活性	5S、23S 及16S rRNA的5'末端成熟	未知	[39]