SKN-1 isoform-c is essential for C. elegans development.

ABSTRACT

The transcription factor SKN-1 in Caenorhabditis elegans is a critical regulator of various biological processes, impacting development, diet and immune responses, cellular detoxification, and lipid metabolism; thereby playing a pivotal role in regulating the health and lifespan of the organism. The primary isoforms of SKN-1 ( SKN-1 a, SKN-1 b, and SKN-1 c) exhibit distinct functions resembling mammalian Nrf transcription factors. This study investigates the specific role of the SKN-1 c isoform in development by generating mutants with targeted missense mutations in the skn-1 c and skn-1 a isoforms. The skn-1 c Met1Ala mutants, which replaces a start methionine with alanine, renders SKN-1 c non-functional while preserving other isoforms, produced inviable embryos, requiring a balancer chromosome for proper embryonic development. In contrast, skn-1 a Met1Ala mutants, which replaces the start methionine with alanine for this isoform, displayed normal embryonic development and hatching. Moreover, the data suggest that SKN-1 c plays a crucial role in embryonic development, as strains without maternally deposited SKN-1 c lead to embryos that are developmentally arrested. Together, these findings contribute to our understanding of SKN-1 c's specific role in influencing embryogenesis and development in C. elegans.