Title

Independent Losses of the Hypoxia-Inducible Factor (HIF) Pathway within Crustacea

Document Type

Journal Article

Publication Date

5-1-2020

Journal

Molecular Biology and Evolution

Volume

37

Issue

5

DOI

10.1093/molbev/msaa008

Keywords

bHLH-PAS; Cirripedia; Copepoda; gene loss; oxygen sensing; transcription factor

Abstract

Metazoans respond to hypoxic stress via the hypoxia-inducible factor (HIF) pathway, a mechanism thought to be extremely conserved due to its importance in monitoring cellular oxygen levels and regulating responses to hypoxia. However, recent work revealed that key members of the HIF pathway have been lost in specific lineages (a tardigrade and a copepod), suggesting that this pathway is not as widespread in animals as previously assumed. Using genomic and transcriptomic data from 70 different species across 12 major crustacean groups, we assessed the degree to which the gene HIFα, the master regulator of the HIF pathway, was conserved. Mining of protein domains, followed by phylogenetic analyses of gene families, uncovered group-level losses of HIFα, including one across three orders within Cirripedia, and in three orders within Copepoda. For these groups, additional assessment showed losses of HIF repression machinery (EGLN and VHL). These results suggest the existence of alternative mechanisms for cellular response to low oxygen and highlight these taxa as models useful for probing these evolutionary outcomes.

This document is currently not available here.

Share

COinS