Zhang Chong, Guo Xinqi, Zhang Ying, Pang Hongbo, Chen Qiang
Department of Life Science, Shenyang Normal University, Shenyang 110034, China.
Experimental Teaching Center, Shenyang Normal University, Shenyang 110034, China.
Int J Mol Sci. 2025 Apr 29;26(9):4254. doi: 10.3390/ijms26094254.
N6-methyladenosine (mA) methylation functions as a vital post-transcriptional and epigenetic modification in higher plants regulated by α-ketoglutarate-dependent dioxygenases (ALKBH). However, the role of ALKBH genes in oriental melon ( L.) fruit ripening has not been explored. Therefore, we treated oriental melon with an exogenous mA demethylase inhibitor (mechlorfenamic acid) then analyzed endogenous ethylene production and ripening-related indicators to explore the effects of mA methylation on ripening. Bioinformatics and real-time quantitative PCR analyses were used to determine the impact of genes on key ethylene synthesis gene expression. Treatment effectively inhibited endogenous ethylene production, firmness changes, and soluble solid contents, thereby extending fruit ripening. Eight gene family members belonging to five major groups were identified in the melon genome. All members were expressed in ripening fruits, with different expression patterns during ripening. , , and expression was inhibited by an ethylene inhibitor (1-methylcyclopropene). The transient overexpression (OE) of in oriental melon led to the increased expression of the ethylene synthesis genes , , and . In summary, the ethylene-regulated gene may participate in oriental melon fruit ripening regulation by modulating the methylation levels of ethylene synthesis-related genes. These findings help us better understand how mA methylation regulates melon ripening.
N6-甲基腺嘌呤（mA）甲基化作为高等植物中一种重要的转录后和表观遗传修饰，受α-酮戊二酸依赖性双加氧酶（ALKBH）调控。然而，ALKBH基因在东方甜瓜果实成熟过程中的作用尚未得到探索。因此，我们用外源mA去甲基化酶抑制剂（甲氯芬那酸）处理东方甜瓜，然后分析内源性乙烯产量和与成熟相关的指标，以探究mA甲基化对成熟的影响。利用生物信息学和实时定量PCR分析来确定ALKBH基因对关键乙烯合成基因表达的影响。处理有效地抑制了内源性乙烯产量、硬度变化和可溶性固形物含量，从而延长了果实成熟时间。在甜瓜基因组中鉴定出属于五个主要类群的八个ALKBH基因家族成员。所有成员均在成熟果实中表达，在成熟过程中具有不同的表达模式。CmALKBH1、CmALKBH2和CmALKBH3的表达受到乙烯抑制剂（1-甲基环丙烯）的抑制。在东方甜瓜中瞬时过表达CmALKBH2导致乙烯合成基因CmACS1、CmACO1和CmACO2的表达增加。总之，乙烯调控基因CmALKBH2可能通过调节乙烯合成相关基因的甲基化水平参与东方甜瓜果实成熟调控。这些发现有助于我们更好地理解mA甲基化如何调控甜瓜成熟。
