The Study Of C. Elegans14-3-3Protein FTT-2and AMPK Protein AAK-2Function In Heat Stress Resistance

Environmental stress such as oxidative stress, hypoxia, and heat shock often causes proteotoxic damage,which triggers the stress-response machinery in order to maintain cellular homeostasis. In this paper, we use C. elegans as a model to study the regulatory mechanism of two conserved proteins14-3-3and AAK-2on heat-resistance. Previous results showed that ftt-2is widely expressed in many tissues, and ftt-2overexpression in pharyngeal muscles can significantly extend life span and increase thermotolerance. This paper firstly analyzed whether the increased thermotolerance by expressing FTT-2in pharyngeal muscles was dependent on the stress regulatory factors daf-16and sir2.1. Our results showed it was dependent on other mechanisms. We next measured the gene expression level of several heat shock protein (HSPs) genes in transgenic strain expressing ftt-2::gfp in pharyngeal muscles by RT-qPCR. Expressing FTT-2in pharyngeal muscle cells can induce higher gene expression of heat shock proteins (HSPs) in response to heat shock treatment, suggesting the increased thermotolerance may be associated with elevated levels of HSPs. In order to further determine aak-2functions on heat shock response regulation, we constructed transgenic lines expressing different aak-2isoforms and distinct structural domains to analyze their rescuing effect on heat-sensitive aak-2mutants, Our results suggested the conserved N-terminal kinase domain and threonine181of AAK-2protein may be important for the heat-resistance regulation. Give the high conservation of14-3-3and AMPK proteins and the fact that stress regulation mechanism may be also highly conserved, our present study will be helpful to further understand regulatory mechanism of two conserved proteins14-3-3and AMPK proteins on stress response.