Evolution of endoglucanase genes in subterranean and surface isopod crustaceans from Central Western Australia
Files
(Published version)
Date
2023
Authors
Javidkar, M.
Cooper, S.J.B.
Shokri Bousjein, N.
Humphreys, W.F.
King, R.A.
Austin, A.D.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Ecology and Evolution, 2023; 13(10):e10552-1-e10552-9
Statement of Responsibility
Mohammad Javidkar, Steven J. B. Cooper, Nahid Shokri Bousjein, William F. Humphreys, Rachael A. King, Andrew D. Austin
Conference Name
Abstract
Recent studies have identified a significant number of endogenous cellulase genes in various arthropods, including isopods, allowing them to process hydrocarbons efficiently as a food source. While this research has provided insight into underlying gene-level processes in cellulose decomposition by arthropods, little is known about the existence and expression of cellulase genes in species from cave environments where carbohydrates are sparse. To investigate whether endogenous cellulase genes are maintained in subterranean species, we sequenced the transcriptomes of two subterranean paraplatyarthrid isopod species from calcrete (carbonate) aquifers of central Western Australia and a related surface isopod species. Seven protein-coding open-reading frames associated with endoglucanase genes were identified in all species. Orthology inference analyses, using a wide range of cellulase sequences from available databases, supported the endogenous origin of the putative endoglucanase genes. Selection analyses revealed that these genes are primarily subject to purifying selection in most of the sites for both surface and subterranean isopod species, indicating that they are likely to encode functional peptides. Furthermore, evolutionary branch models supported the hypothesis of an adaptive shift in selective pressure acting on the subterranean lineages compared with the ancestral lineage and surface species. Branch-site models also revealed a few amino acid sites on the subterranean branches to be under positive selection, suggesting the acquisition of novel adaptations to the subterranean environments. These findings also imply that hydrocarbons exist in subsurface aquifers, albeit at reduced levels, and have been utilized by subterranean isopods as a source of energy for millions of years.
School/Discipline
Dissertation Note
Provenance
Description
Access Status
Rights
© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.