EAPSI: Investigating the production of stress-induced proteins following nitrite exposure in the commonly farmed shrimp Litopenaeus vannamei

Wang Jason, Charleston SC

Investigators

Abstract

Farmed shrimp comprises a significant portion of global food production, and most of shrimp production comes from Pacific countries such as Taiwan. Aquaculture facilities commonly stock shrimp in unnaturally high densities and produce excessive organic wastes. Shrimp excrete ammonia waste, which is converted to nitrite by microbes. Nitrite accumulates inside the shrimp, causing damage to proteins and cells. In many animals, a common response to stress is the production of a class of proteins called heat shock proteins (HSP). These proteins preserve the shape and function of damaged proteins. However, little is understood about the role of HSPs in aquacultured shrimp. This study aims to quantify the production of HSPs in several shrimp tissues following nitrite stress exposures. This study will be conducted in Taiwan in collaboration with Dr. Cheng-Hao Tang (Institute of Marine Biotechnology, National Dong Hwa University), an expert in stress responses of aquacultured animals. Understanding how HSPs alleviate stress in shrimp will elucidate the effects that aquaculture conditions have on commercially important organisms and their surrounding environments. Nitrite is an important stressor because it is a common byproduct of microbial metabolism in marine systems, and also a reactive oxidative species. In aquaculture ponds, nitrite can reach an excess of 20 mg mL-1, easily entering the shrimp's system through the gills. This study will quantify production of four different HSP mRNA transcripts and proteins using quantitative PCR and Western Blots. Quantification of HSP transcripts and proteins will be done in the gills and the hepatopancreas where enzymes are produced. Nitrite is one of many stressors that may induce HSP production, and this work will further the framework for examining diverse stress responses using HSPs. The NSF EAPSI award is funded in collaboration with the National Science Council of Taiwan.