Investigation of the effect of ocean acidification on the haemocyte proteome of the South African abalone, Haliotis midae

• Main Author: Carroll,SarahLeigh
• Other Authors: Coyne, Vernon
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Faculty of Science 2020
• Subjects: Molecular and Cell Biology; Ocean acidification
• Online Access: http://hdl.handle.net/11427/36689; https://open.uct.ac.za/bitstream/11427/36689/1/thesis_sci_2020_carrollsarahleigh.pdf

Haliotis midae is an economically important marine invertebrate that is farmed in South Africa, contributing more than half of the revenue generated by the aquaculture industry. However, the future sustainability of abalone farming in South Africa is threatened by the ongoing climate crisis. The effect of climate change is unrelenting for organisms such as abalone, which rely on a succinct balance of physico-chemical environmental properties. Indeed, the ocean environment is susceptible to these imbalances and has already witnessed changes in seawater temperatures and pH. Over the last century, global ocean surface temperatures have increased by 0.74°C and seawater pH has declined by 0.1 units, while global predictions for 2100 suggest oceans will experience a decline in pH by 0.3-0.5 units. Thus, ocean acidification (OA) is a growing cause for concern since it adversely affects marine organisms such as corals and calcareous marine invertebrates. Research focusing on the effect of climate change on marine life has grown tremendously over the last two decades, with an emphasis on molluscs such as mussels and oysters which are considered ideal proxies for measuring environmental change and the underlying molecular effects thereof. However, research on abalone in this arena has primarily focused on larvae and the physiological effects of OA on development and shell growth. The underlying molecular mechanisms involved in the Haliotis midae stress response to ocean acidification have largely remained unexplored. Thus, this study sought to elucidate the effect of OA on the haemocyte proteome of H. midae, as well as to gain insight into the underlying molecular mechanisms that characterize the stress response of this abalone species. This study employed a comparative shotgun proteomics approach using isobaric tagging for relative and absolute quantification (iTRAQ) coupled with LC-MS/MS to investigate the proteomic response of H. midae haemocytes to reduced pH conditions representative of future predictions of ocean ...