Genome-Wide Role of HSF1 in Transcriptional Regulation of Desiccation Tolerance in the Anhydrobiotic Cell Line, Pv11.

Shoko Tokumoto,Ruslan Deviatiiarov,Oleg Gusev,Akira Funahashi,Yuki Yoshida,Yugo Miyata,Richard Cornette,Takahiro Kikawada,Yusuke Hiki,Takahiro G Yamada,Olga Kozlova,Elena Shagimardanova

doi:10.3390/ijms22115798

Abstract

The Pv11, an insect cell line established from the midge Polypedilum vanderplanki, is capable of extreme hypometabolic desiccation tolerance, so-called anhydrobiosis. We previously discovered that heat shock factor 1 (HSF1) contributes to the acquisition of desiccation tolerance by Pv11 cells, but the mechanistic details have yet to be elucidated. Here, by analyzing the gene expression profiles of newly established HSF1-knockout and -rescue cell lines, we show that HSF1 has a genome-wide effect on gene regulation in Pv11. The HSF1-knockout cells exhibit a reduced desiccation survival rate, but this is completely restored in HSF1-rescue cells. By comparing mRNA profiles of the two cell lines, we reveal that HSF1 induces anhydrobiosis-related genes, especially genes encoding late embryogenesis abundant proteins and thioredoxins, but represses a group of genes involved in basal cellular processes, thus promoting an extreme hypometabolism state in the cell. In addition, HSF1 binding motifs are enriched in the promoters of anhydrobiosis-related genes and we demonstrate binding of HSF1 to these promoters by ChIP-qPCR. Thus, HSF1 directly regulates the transcription of anhydrobiosis-related genes and consequently plays a pivotal role in the induction of anhydrobiotic ability in Pv11 cells.

Highlights

Whereas a single 2928-bp band was detected in the Hsf1−/− cell line, a single 191-bp band was detected in wild type (WT) Pv11 cells (Figure 1b)
Only 3, 1, 5 and 1 of the Pimt, Lil, heat shock protein (Hsp) and trehalose metabolism-related genes, respectively, were strongly upregulated. These results showed that the expression of Lea and Trx genes is more dependent on heat shock factor 1 (HSF1) than that of Pimt, Lil, Hsp and trehalose metabolism-related genes in Pv11 cells
We demonstrate the successful establishment of HSF1-knockout (Hsf1−/− and Hsf1−/− ; HaloTag/blasticidin S-resistance (BlaR)) and -rescue (Hsf1−/− ; Hsf1-HaloTag/BlaR) cell lines using the CRIS-PITCh system [34,35] (Figures 1 and 2) and investigate the contribution of HSF1 to the gene regulation required for anhydrobiosis in

Summary

Introduction

Anhydrobiosis is a reversible extreme hypometabolic state characterized by almost completely stopped metabolism and extreme loss of body water, generally over 95%, due to desiccation [1,2,3]. The anhydrobiotic state enables organisms to withstand long-term drought and to return to a normal life cycle after rehydration [4]. The larva of the sleeping chironomid Polypedilum vanderplanki [10], which inhabits semi-arid regions of Africa, is anhydrobiotic [11,12,13]. The cell line, Pv11, which was derived from P. vanderplanki embryos, is capable of the extreme desiccation tolerance that characterizes anhydrobiosis [14,15]. Pv11 is a promising model in which to investigate the molecular mechanisms underlying anhydrobiosis in

Methods

Results

Conclusion