Document Type

Journal Article

Department/Unit

Department of Biology

Language

English

Abstract

Although high-throughput proteomics has been widely applied to study mechanisms of environmental adaptation, the conclusions from studies that are based on one species can be confounded by phylogeny. We compare the freshwater snail Pomacea canaliculata (a notorious invasive species) and its congener Pomacea diffusa (a non-invasive species) to understand the molecular mechanisms of their differential resistance to hypoxia. A 72-h acute exposure experiment showed that P. canaliculata is more tolerant to hypoxia than P. diffusa. The two species were then exposed to three levels of dissolved oxygen (6.7, 2.0 and 1.0mgL-1) for 8h, and their gill proteins were analyzed using iTRAQ-coupled LC-MS/MS. The two species showed striking differences in protein expression profiles, with the more hypoxia tolerant P. canaliculata having more up-regulated proteins in signal transduction and down-regulated proteins in glycolysis and the tricarboxylic acid cycle. Evolutionary analysis revealed five orthologous genes encoding differentially expressed proteins having clear signal of positive selection, indicating selection has acted on some of the hypoxia responsive genes. Our case study has highlighted the potential of integrated proteomics and comparative evolutionary analysis for understanding the genetic basis of adaptation to global environmental change in non-model species. Significance: Rapid globalization in recent decades has greatly facilitated species introduction around the world. Successfully established introduced species, so-called invasive species, have threatened the invaded ecosystems. There has been substantial interest in studying how invasive species respond to extreme environmental conditions because the results can help not only predict their range of expansion and manage their impact, but also may reveal the adaptive mechanisms underlying their invasiveness. Our study has adopted a comparative approach to study the differential physiological and proteomic responses of two congeneric snails to various hypoxic conditions, as well as codon substitution analysis at transcriptomic level to detect signals of positive selection in hypoxia-responsive genes. The integrated physiological, proteomic and transcriptomic approach can be applied in other non-model species to understand the molecular mechanisms of adaptation to global environmental change.

Keywords

Epigenetics, Invasive species, Pomacea, Proteomics, Stress response

Publication Date

2-10-2018

Source Publication Title

Journal of Proteomics

Volume

172

Start Page

36

End Page

48

Peer Reviewed

1

Copyright

© 2017 Elsevier B.V. All rights reserved.

Funder

This work was supported by the General Research Fund of Hong Kong (grant no. HKBU261312 and HKBU12301415) and Hong Kong Baptist University (grant no. SDF 15-1012-P04).

DOI

10.1016/j.jprot.2017.11.002

Link to Publisher's Edition

http://dx.doi.org/10.1016/j.jprot.2017.11.002

ISSN (print)

18743919

ISSN (electronic)

1876-7737

Available for download on Friday, March 01, 2019

Included in

Biology Commons

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