A proteomic investigation of the immune response of the South African abalone, Haliotis midae

Haliotis midae is a commercially important abalone in South Africa, previously harvested from a stable, quota-managed fishery. However, the combined effects of overharvesting, increased illegal catches and negative environmental factors led to a collapse in wild populations in the mid-90s. Consequently, land-based aquaculture of H. midae has grown significantly in South Africa, to satisfy the global demand for abalone and alleviate pressure on wild stocks. Unfortunately, disease outbreaks have had a severe impact on the abalone aquaculture industry internationally and remain one of the single biggest factors contributing to economic loss. Understanding the effects of pathogen infection of abalone is therefore crucial to mitigating and controlling infection outbreaks on farms. Despite this, the molecular mechanisms underlying the immune response of H. midae remain obscure. High-throughput proteomics, a powerful tool to analyse global protein expression changes, can provide an integrated view of the immune system. Thus, this study aimed to elucidate the haemocyte proteome of H. midae and gain insight into regulatory molecular pathways underlying innate immunity. In this study, a comparative shotgun proteomics approach using isobaric tagging for relative and absolute quantification (iTRAQ) coupled with LC-MS/MS was employed to investigate H. midae proteome changes in response to Vibrio anguillarum challenge. A preliminary iTRAQ challenge trial was conducted which identified a putative early (1 and 2 hours post-injection) and late (48 hours post-injection) proteome response to bacterial-challenge. Using these time points, four independent challenge trials were conducted and analysed by iTRAQ and the results combined to produce a high-confidence dataset with good quantitative reproducibility for statistical analysis. A parallel set of experiments was conducted using mock-infected samples.

Grantor dc:publisher.institution

Department of English Language and Literature

Year dc:date.issued

2015

Author dc:creator

• Beltran, Caroline Gina Gracieuse

Advisor dc:contributor.advisor

• Coyne, Vernon

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/16483

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/16483