Alternative splicing diversifies HSF1 function to enable desiccation tolerance of P. vanderplanki cells

Here we report the identification of five alternative splicing isoforms of P. vanderplanki HSF1 (PvHSF1) and their distinct functional roles during anhydrobiosis cycle and heat shock in Pv11 cells, derived from P. vanderplanki. All five PvHSF1 isoforms induced desiccation tolerance, but with varible efficiency followed by distinct gene expression patterns.

We revealed that PvHSF1 isoform 2 is the most abundant isoform in the anhydrobiosis state. It directly regulates gene esxpression resulting in both activation and suppression. Other two PvHSF1 isoforms (1 and 3) were responsible for cell adaptation to severe heat shock by modulating expression of genes.