Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada.
Genes (Basel). 2024 Sep 1;15(9):1156. doi: 10.3390/genes15091156.
The African clawed frog () endures prolonged periods of dehydration while estivating underground during the dry season. Epigenetic modifications play crucial roles in regulating gene expression in response to environmental changes. The elucidation of epigenetic changes relevant to survival could serve as a basis for further studies on organ preservation under extreme stress. The current study examined the relative protein levels of key enzymes involved in the arginine methylation of histones in the liver and kidney tissues of control versus dehydrated (35 ± 1%) through immunoblotting. Protein arginine methyltransferases (PRMT) 4, 5, and 6 showed significant protein level decreases of 35 ± 3%, 71 ± 7%, and 25 ± 5%, respectively, in the liver tissues of the dehydrated frogs relative to controls. In contrast, PRMT7 exhibited an increase of 36 ± 4%. Similarly, the methylated histone markers H3R2m2a, H3R8m2a, and H3R8m2s were downregulated by 34 ± 11%, 15 ± 4%, and 42 ± 12%, respectively, in the livers of dehydrated frogs compared to controls. By contrast, the kidneys of dehydrated frogs showed an upregulation of histone markers. H3R2m2a, H3R8m2a, H3R8m2s, and H4R3m2a were significantly increased by 126 ± 12%, 112 ± 7%, 47 ± 13%, and 13 ± 3%, respectively. These changes can play vital roles in the metabolic reorganization of during dehydration, and are likely to increase the chances of survival. In turn, the tissue-specific regulation of the histone arginine methylation mechanism suggests the importance of epigenetic regulation in the adaptation of for whole-body dehydration.
爪蟾在旱季会在地下进行夏眠，以忍受长时间的脱水。表观遗传修饰在调节基因表达以响应环境变化方面起着至关重要的作用。阐明与生存相关的表观遗传变化可以为进一步研究在极端应激下器官保存提供基础。本研究通过免疫印迹法检测了对照组与脱水组（35±1%）肝脏和肾脏组织中关键酶的相对蛋白水平，这些酶参与组蛋白精氨酸甲基化。蛋白精氨酸甲基转移酶（PRMT）4、5 和 6 在脱水青蛙的肝脏组织中分别显示出 35±3%、71±7%和 25±5%的显著蛋白水平降低，而 PRMT7 则表现出 36±4%的增加。同样，甲基化组蛋白标记物 H3R2m2a、H3R8m2a 和 H3R8m2s 在脱水青蛙的肝脏中分别下调了 34±11%、15±4%和 42±12%，而在对照组中则上调了 34±11%、15±4%和 42±12%。相比之下，脱水青蛙的肾脏显示出组蛋白标记物的上调。H3R2m2a、H3R8m2a、H3R8m2s 和 H4R3m2a 分别显著增加了 126±12%、112±7%、47±13%和 13±3%。这些变化在脱水期间可能对 代谢重排起着至关重要的作用，并可能增加其生存机会。反过来，组蛋白精氨酸甲基化机制的组织特异性调节表明了表观遗传调节在 适应全身脱水方面的重要性。
