Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, Hebei Collaborative Innovation Center for Eco-Environment, Hebei Research Center of the Basic Discipline of Cell Biology, Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China.
The Professional and Technical Center of Hebei Administration for Market Regulation, Shijiazhuang, 050024, China.
Parasit Vectors. 2024 May 12;17(1):218. doi: 10.1186/s13071-024-06288-4.
Epigenetic modifications of histones play important roles in the response of eukaryotic organisms to environmental stress. However, many histone acetyltransferases (HATs), which are responsible for histone acetylation, and their roles in mediating the tick response to cold stress have yet to be identified. In the present study, HATs were molecularly characterized and their associations with the cold response of the tick Haemaphysalis longicornis explored.
HATs were characterized by using polymerase chain reaction (PCR) based on published genome sequences, followed by multiple bioinformatic analyses. The differential expression of genes in H. longicornis under different cold treatment conditions was evaluated using reverse transcription quantitative PCR (RT-qPCR). RNA interference was used to explore the association of HATs with the cold response of H. longicornis.
Two HAT genes were identified in H. longicornis (Hl), a GCN5-related N-acetyltransferase (henceforth HlGNAT) and a type B histone acetyltransferase (henceforth HlHAT-B), which are respectively 960 base pairs (bp) and 1239 bp in length. Bioinformatics analysis revealed that HlGNAT and HlHAT-B are unstable hydrophilic proteins characterized by the presence of the acetyltransferase 16 domain and Hat1_N domain, respectively. RT-qPCR revealed that the expression of HlGNAT and HlHAT-B decreased after 3 days of cold treatment, but gradually increased with a longer period of cold treatment. The mortality rate following knockdown of HlGNAT or HlHAT-B by RNA interference, which was confirmed by RT-qPCR, significantly increased (P < 0.05) when H. longicornis was treated at the lowest lethal temperature (- 14 °C) for 2 h.
The findings demonstrate that HATs may play a crucial role in the cold response of H. longicornis. Thus further research is warranted to explore the mechanisms underlying the epigenetic regulation of the cold response in ticks.
组蛋白的表观遗传修饰在真核生物对环境胁迫的反应中起着重要作用。然而，许多负责组蛋白乙酰化的组蛋白乙酰转移酶（HATs）及其在介导蜱对冷应激反应中的作用尚未被确定。在本研究中，通过基于已发表基因组序列的聚合酶链反应（PCR）对 HATs 进行了分子特征分析，并探讨了其与蜱的冷应激反应的关系。
通过基于已发表基因组序列的聚合酶链反应（PCR）对 HATs 进行了分子特征分析，随后进行了多种生物信息学分析。采用反转录定量 PCR（RT-qPCR）评估了不同冷处理条件下长角血蜱（Haemaphysalis longicornis）中基因的差异表达。采用 RNA 干扰技术探讨了 HATs 与长角血蜱冷应激反应的关系。
在长角血蜱（Hl）中鉴定出了两个 HAT 基因，一个是 GCN5 相关的 N-乙酰转移酶（简称 HlGNAT），另一个是 B 型组蛋白乙酰转移酶（简称 HlHAT-B），它们分别长 960 个碱基对（bp）和 1239 bp。生物信息学分析表明，HlGNAT 和 HlHAT-B 是不稳定的亲水蛋白，分别具有乙酰转移酶 16 结构域和 Hat1_N 结构域。RT-qPCR 显示，在冷处理 3 天后，HlGNAT 和 HlHAT-B 的表达下降，但随着冷处理时间的延长逐渐增加。通过 RNA 干扰确认 HlGNAT 或 HlHAT-B 的敲低后，长角血蜱在最低致死温度（-14°C）下处理 2 小时时的死亡率显著升高（P<0.05）。
研究结果表明，HATs 可能在长角血蜱的冷应激反应中发挥关键作用。因此，有必要进一步研究以探索蜱类冷应激反应中的表观遗传调控机制。
