面对全球气温上升,生物体适应热应激的能力背后的机制仍然是神秘的。稻叶夹,稻长,传统上被视为对温度敏感,矛盾的是,幼虫对热应激表现出强烈的适应能力。这项研究使用了热适应的菌株HA39,该菌株是通过在幼虫阶段多代暴露于39°C而开发的,未适应的菌株HA27在27°C下饲养,以揭示热适应的跨代效应及其调节机制。幼虫的热适应在暴露于高温时会在p中产生健身成本,然而,显著的跨代效应浮出水面,即使在27°C的幼虫恢复过程中没有额外的热暴露,也显示出来自HA39的p的健康益处。这种跨代效应表现出短期记忆,在经历了两代的恢复之后,此外,该效应与超氧化物歧化酶(SOD)酶活性和氧化还原酶基因表达水平增加相关,代表热适应的生理和分子基础。热适应的幼虫显示DNA甲基化水平升高,而来自HA39的p,在恢复世代中,在高温下,去甲基酶基因的上调和两个甲基转移酶基因的下调表明甲基化降低。总之,热适应诱导DNA甲基化,协调热应激记忆并影响氧化还原酶基因和SOD活性的表达水平。热应激记忆增强了移栖害虫对全球变暖的适应。
In the face of rising global temperatures, the mechanisms behind an organism\'s ability to acclimate to heat stress remain enigmatic. The rice leaf folder, Cnaphalocrocis medinalis, traditionally viewed as temperature-sensitive, paradoxically exhibits robust larval acclimation to heat stress. This study used the heat-acclimated strain HA39, developed through multigenerational exposure to 39°C during the larval stage, and the unacclimated strain HA27 reared at 27°C to unravel the transgenerational effects of heat acclimation and its regulatory mechanisms. Heat acclimation for larvae incurred a fitness cost in pupae when exposed to high temperature, yet a significant transgenerational effect surfaced, revealing heightened fitness benefit in pupae from HA39, even without additional heat exposure during larval recovery at 27°C. This transgenerational effect exhibited a short-term memory, diminishing after two recovery generations. Moreover, the effect correlated with increased superoxide dismutase (SOD) enzyme activity and expression levels of oxidoreductase genes, representing physiological and molecular foundations of heat acclimation. Heat-acclimated larvae displayed elevated DNA methylation levels, while pupae from HA39, in recovery generations, exhibited decreased methylation indicated by the upregulation of a demethylase gene and downregulation of two methyltransferase genes at high temperatures. In summary, heat acclimation induces DNA methylation, orchestrating heat-stress memory and influencing the expression levels of oxidoreductase genes and SOD activity. Heat-stress memory enhances the acclimation of the migratory insect pest to global warming.