果实成熟过程中的DNA甲基化调控研究进展

doi:10.16420/j.issn.0513-353x.2021-1130

摘要/Abstract

摘要：

DNA甲基化是一种常见的表观遗传修饰，对植物果实的成熟具有重要的作用，本文中综述了果实成熟过程中DNA甲基化水平的变化及其调控机制。基于已有研究发现，大部分果实在成熟过程存在总体DNA甲基化水平降低的情况，也有部分果实的总体DNA甲基化水平随果实成熟呈现升高趋势。此外，在果实成熟过程中特定基因尤其是与成熟相关的基因在去甲基化酶作用下发生去甲基化进而影响果实成熟。引起果实成熟过程中DNA甲基化水平变化的机制总体而言是受到甲基化酶、去甲基化酶以及植物特有的RdDM途径的综合调控。本文为深入解析果实发育与成熟的分子机制提供理论参考，并对以后的研究提出可行的建议。

关键词: 果实, 成熟, DNA甲基化, 表观遗传调控

Abstract:

DNA methylation is an important epigenetic modification，playing critical roles during fruit ripening. Here we reviewed the changes and mechanism of DNA methylation during fruit ripening in different fruits. Based on previous studies，it was found that the total DNA methylation level in most fruits decreases during the ripening process while the overall DNA methylation increases in a few other fruits. In addition，specific genes，especially those related to ripening，undergo demethylation under the regulation of demethylase，which further affects fruit ripening. In general，the mechanism that causes DNA methylation alternations during fruit ripening is comprehensively regulated by methylase，demethylase and plant specific RdDM pathway. This work provides important theoretical reference for the epigenetic regulation mechanism of fruit ripening，and feasible suggestions are proposed for future work.

Key words: fruit, ripening, DNA methylation, epigenetic regulation

中图分类号:

S6
Q945.65

邵凤清, 罗秀荣, 王奇, 张宪智, 王文彩. 果实成熟过程中的DNA甲基化调控研究进展[J]. 园艺学报, 2023, 50(1): 197-208.

SHAO Fengqing, LUO Xiurong, WANG Qi, ZHANG Xianzhi, WANG Wencai. Advances in Research of DNA Methylation Regulation During Fruit Ripening[J]. Acta Horticulturae Sinica, 2023, 50(1): 197-208.

图/表 3

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类别 Category	名称 Name	代表成员 Representative	主要功能 Major function	参考文献 Reference
DNA甲基化酶 DNA methylase	甲基转移酶 Methyl-transferase，MET	MET1	主要催化并维持对称位点CG胞嘧啶的甲基化 MET1 mainly catalyzes and maintains the methylation of CG cytosine at symmetric sites	Zubko et al.，2012
	染色质甲基化酶 Chromomethylase，CMT	CMT3/2	CMT3主要对着丝粒附近重复区和转座子序列的CHG进行甲基化修饰 CMT3 mainly methylates CHGS in repeat regions near centromeres and transposon sequences	Lindroth et al.，2001;Tompa et al.，2002
	染色质甲基化酶 Chromomethylase，CMT	CMT3/2	CMT2催化非对称位点CHH的从头甲基化 CMT2 catalyzes de novo methylation of CHH at asymmetric sites	Stroud et al.，2014
	结构域重排甲基转移酶 Domains rearranged methylase，DRM	DRM1/2	DRM1和DRM2催化非对称位点CHH的从头甲基化 DRM1 and DRM2 catalyze de novo methylation of CHH at asymmetric sites	Cao & Jacobsen，2002;B?hmdorfer et al.，2016
DNA去甲基化酶 DNA demethylase	DNA糖苷酶-裂解酶（DEMETER-like DNA去甲基化酶） DNA Glycosylase-lyases（DEMETER-like DNA demethylases，DMLs）	ROS1（Repressor of silencing 1）	识别并去除双链DNA寡核苷酸中的甲基化胞嘧啶 ROS1 recognizes and removes cytosines methylation in double-stranded DNA oligonucleotides	Gong et al.，2002
		DML1/2/3/4	番茄中的DNA去甲基化酶具有DNA糖苷化酶/裂解酶的功能区 DMLs in tomatoes has a functional region for DNA glycosidase/lyase	Liu et al.，2015
		SlDML1/2/3/4	番茄SlDML1和SlDML2是拟南芥ROS1（AtROS1）的同源基因，SlDML3是拟南芥AtDME（DEMETER）的同源基因，SlDML2能促进番茄成熟 SlDML1 and SlDML2，SlDML3 in tomato are homologous genes of ROS1（AtROS1）and AtDME（DEMETER）in Arabidopsis Thaliana respectively；SlDML2 promotes tomato ripening	Liu et al.，2015

类别 Category	名称 Name	代表成员 Representative	主要功能 Major function	参考文献 Reference
DNA甲基化酶 DNA methylase	甲基转移酶 Methyl-transferase，MET	MET1	主要催化并维持对称位点CG胞嘧啶的甲基化 MET1 mainly catalyzes and maintains the methylation of CG cytosine at symmetric sites	Zubko et al.，2012
	染色质甲基化酶 Chromomethylase，CMT	CMT3/2	CMT3主要对着丝粒附近重复区和转座子序列的CHG进行甲基化修饰 CMT3 mainly methylates CHGS in repeat regions near centromeres and transposon sequences	Lindroth et al.，2001;Tompa et al.，2002
	染色质甲基化酶 Chromomethylase，CMT	CMT3/2	CMT2催化非对称位点CHH的从头甲基化 CMT2 catalyzes de novo methylation of CHH at asymmetric sites	Stroud et al.，2014
	结构域重排甲基转移酶 Domains rearranged methylase，DRM	DRM1/2	DRM1和DRM2催化非对称位点CHH的从头甲基化 DRM1 and DRM2 catalyze de novo methylation of CHH at asymmetric sites	Cao & Jacobsen，2002;B?hmdorfer et al.，2016
DNA去甲基化酶 DNA demethylase	DNA糖苷酶-裂解酶（DEMETER-like DNA去甲基化酶） DNA Glycosylase-lyases（DEMETER-like DNA demethylases，DMLs）	ROS1（Repressor of silencing 1）	识别并去除双链DNA寡核苷酸中的甲基化胞嘧啶 ROS1 recognizes and removes cytosines methylation in double-stranded DNA oligonucleotides	Gong et al.，2002
		DML1/2/3/4	番茄中的DNA去甲基化酶具有DNA糖苷化酶/裂解酶的功能区 DMLs in tomatoes has a functional region for DNA glycosidase/lyase	Liu et al.，2015
		SlDML1/2/3/4	番茄SlDML1和SlDML2是拟南芥ROS1（AtROS1）的同源基因，SlDML3是拟南芥AtDME（DEMETER）的同源基因，SlDML2能促进番茄成熟 SlDML1 and SlDML2，SlDML3 in tomato are homologous genes of ROS1（AtROS1）and AtDME（DEMETER）in Arabidopsis Thaliana respectively；SlDML2 promotes tomato ripening	Liu et al.，2015

DNA甲基化变化 DNA demethylation changes	物种 Species	机制 Mechanism	参考文献 Reference
去甲基化 Demethylation	番茄 Tomato	SlDML2去甲基化酶介导DNA去甲基化 DNA demethylation mediated by SlDML2 demethylase	Teyssier et al.，2008;Zhong et al.，2013; Liu et al.，2015;Lang et al.，2017
	桑葚 Mulberry	/	方立静，2020
	‘巨峰’葡萄 ‘Kyoho’grape berry	/	李琼，2019
	辣椒 Pepper	/	李宁等，2018
	水稻、拟南芥 Rice，Arabidopsis	/	Zemach et al.，2010;Law & Jacobsen，2010;Feng et al.，2010
	草莓 Strawberry	RdDM下调介导的DNA去甲基化 DNA demethylation mediated by RdDM downregulation	Cheng et al.，2018
	苹果 Apple	/	Telias et al.，2011;El-Sharkawy et al.，2015
	温州蜜柑 Satsuma	/	陈志友，2014
	番木瓜 Papaya fruit		周陈平等，2022
甲基化升高 Increasing methylation	紫玉米 Purple corn	/	李廷春等，2014
	柑橘 Citrus	/	徐记迪，2015
	甜橙 Orange	DNA去甲基化酶表达下降 Decreased expression of DNA demethylase	Huang et al.，2019

DNA甲基化变化 DNA demethylation changes	物种 Species	机制 Mechanism	参考文献 Reference
去甲基化 Demethylation	番茄 Tomato	SlDML2去甲基化酶介导DNA去甲基化 DNA demethylation mediated by SlDML2 demethylase	Teyssier et al.，2008;Zhong et al.，2013; Liu et al.，2015;Lang et al.，2017
	桑葚 Mulberry	/	方立静，2020
	‘巨峰’葡萄 ‘Kyoho’grape berry	/	李琼，2019
	辣椒 Pepper	/	李宁等，2018
	水稻、拟南芥 Rice，Arabidopsis	/	Zemach et al.，2010;Law & Jacobsen，2010;Feng et al.，2010
	草莓 Strawberry	RdDM下调介导的DNA去甲基化 DNA demethylation mediated by RdDM downregulation	Cheng et al.，2018
	苹果 Apple	/	Telias et al.，2011;El-Sharkawy et al.，2015
	温州蜜柑 Satsuma	/	陈志友，2014
	番木瓜 Papaya fruit		周陈平等，2022
甲基化升高 Increasing methylation	紫玉米 Purple corn	/	李廷春等，2014
	柑橘 Citrus	/	徐记迪，2015
	甜橙 Orange	DNA去甲基化酶表达下降 Decreased expression of DNA demethylase	Huang et al.，2019