Effects of cold-acclimation on gene expression in Fall field cricket (Gryllus pennsylvanicus) ionoregulatory tissues

BMC Genomics

Research Article

Lauren E. Des Marteaux¹  Jantina Toxopeus¹  Brent J. Sinclair¹  Alexander H McKinnon²  Hiroko Udaka³ 

[1] Department of Biology, The University of Western Ontario, London, ON, Canada;Department of Biology, The University of Western Ontario, London, ON, Canada;Present Address: Faculty of Medicine, University of Manitoba, Winnipeg, MB, Canada;Department of Biology, The University of Western Ontario, London, ON, Canada;Present Address: Graduate School of Science, Biological Sciences, Kyoto University, Kyoto, Japan;

关键词: Insect;    Cold tolerance;    RNA-Seq;    Acclimation;    Ion pump;    Malpighian tubules;    Rectum;    Phenotypic plasticity;    Gryllus;   

DOI  :  10.1186/s12864-017-3711-9

 received in 2016-08-18, accepted in 2017-04-20,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundCold tolerance is a key determinant of temperate insect distribution and performance. Chill-susceptible insects lose ion and water homeostasis during cold exposure, but prior cold acclimation improves both cold tolerance and defense of homeostasis. The mechanisms underlying these processes are mostly unknown; cold acclimation is thought to enhance ion transport in the cold and/or prevent leak of water and ions. To identify candidate mechanisms of cold tolerance plasticity we generated transcriptomes of ionoregulatory tissues (hindgut and Malpighian tubules) from Gryllus pennsylvanicus crickets and compared gene expression in warm- and cold-acclimated individuals.ResultsWe assembled a G. pennsylvanicus transcriptome de novo from 286 million 50-bp reads, yielding 70,037 contigs (~44% of which had putative BLAST identities). We compared the transcriptomes of warm- and cold-acclimated hindguts and Malpighian tubules. Cold acclimation led to a ≥ 2-fold change in the expression of 1493 hindgut genes (733 downregulated, 760 upregulated) and 2008 Malpighian tubule genes (1009 downregulated, 999 upregulated). Cold-acclimated crickets had altered expression of genes putatively associated with ion and water balance, including: a downregulation of V-ATPase and carbonic anhydrase in the Malpighian tubules and an upregulation of Na+-K+ ATPase in the hindgut. We also observed acclimation-related shifts in the expression of cytoskeletal genes in the hindgut, including actin and actin-anchoring/stabilizing proteins, tubulin, α-actinin, and genes involved in adherens junctions organization. In both tissues, cold acclimation led to differential expression of genes encoding cytochrome P450s, glutathione-S-transferases, apoptosis factors, DNA repair, and heat shock proteins.ConclusionsThis is the first G. pennsylvanicus transcriptome, and our tissue-specific approach yielded new candidate mechanisms of cold tolerance plasticity. Cold acclimation may reduce loss of hemolymph volume in the cold by 1) decreasing primary urine production via reduced expression of carbonic anhydrase and V-ATPase in the Malpighian tubules and 2) by increasing Na+ (and therefore water) reabsorption across the hindgut via increase in Na+-K+ ATPase expression. Cold acclimation may reduce chilling injury by remodeling and stabilizing the hindgut epithelial cytoskeleton and cell-to-cell junctions, and by increasing the expression of genes involved in DNA repair, detoxification, and protein chaperones.

【 授权许可】

CC BY   
© The Author(s). 2017