Hwang Ho-Yon, Dankovich Laura, Wang Jiou
Department of Biochemistry and Molecular Biology, Johns Hopkins University, Baltimore, MD, United States.
Department of Neuroscience, Johns Hopkins University, Baltimore, MD, United States.
Front Genet. 2020 Oct 6;11:566948. doi: 10.3389/fgene.2020.566948. eCollection 2020.
Thermotolerance of an organism is a complex trait that is influenced by a multitude of genetic and environmental factors. Many factors controlling thermotolerance in are known to extend life. To understand the regulation of thermotolerance, we performed a genetic screen for mutants with better survival at warm temperature. Here we identified by dauer survival a mutation and several mutations disrupting an insulin signaling pathway including the gene. While the mutant has improved thermotolerance and long life span, the newly identified and other insulin signaling mutants, unlike the canonical , do not show improved thermotolerance despite being long-lived. Examination of mutations and their mutant phenotypes suggest that the control of thermotolerance is not coupled with the control of life span or dauer survival. With genetic interaction studies, we concluded that has complex roles in life span and dauer survival and that is a negative regulator of thermotolerance independent of other known thermotolerance genes including those in the insulin signaling pathway. Moreover, cold growth temperature during development weakens the improved thermotolerance associated with and other thermotolerance-inducing mutations. Together, this study reveals previously unknown genetic and environmental factors controlling thermotolerance and their complex relationship with life span regulation.
生物体的耐热性是一种复杂的性状，受到多种遗传和环境因素的影响。已知许多控制耐热性的因素能够延长寿命。为了理解耐热性的调控机制，我们针对在温暖温度下具有更好存活率的突变体进行了遗传筛选。在此，我们通过 dauer 存活率鉴定出一个突变以及几个破坏胰岛素信号通路（包括 基因）的突变。虽然 突变体具有提高的耐热性和较长的寿命，但新鉴定出的 以及其他胰岛素信号突变体，与典型的 不同，尽管寿命较长，但并未表现出耐热性的提高。对 突变及其突变体表型的研究表明，耐热性的控制与寿命或 dauer 存活率的控制并无关联。通过遗传相互作用研究，我们得出结论， 在寿命和 dauer 存活率方面具有复杂的作用，并且 是耐热性的负调控因子，独立于其他已知的耐热性基因，包括胰岛素信号通路中的那些基因。此外，发育过程中的低温生长温度会削弱与 和其他耐热性诱导突变相关的耐热性提高。总之，这项研究揭示了以前未知的控制耐热性的遗传和环境因素及其与寿命调控的复杂关系。
