Abstract

Analysis of Immune Genes and Heat Shock Protein Genes under Exposure to White Spot Syndrome Virus (WSSV) and Herbal Immune Stimulant in Litopenaeus vannamei

Venkatesan C, Sahul Hameed AS, N Sundarraj, T Rajkumar and G Balasubramanian

This work was carried out to analysis of immune genes (Lectin (245 bp), PoPO (121 bp), BGBP (166 bp), hemocyanin (242 bp), Toll receptor (150 bp) and immunological analysis in white shrimp (Litopenaeus vannamei) infected with WSSV and herbal immune stimulant (immuzone) treated. And also to understand the level of expression and distribution of Heat Shock Proteins (Hsp) in white shrimp (Litopenaeus vannamei). Under untreated condition, all the immune genes (Lectin, PoPO, BGBP, hemocyanin, Toll receptor) were differentially expressed in all of the examined tissues. Under WSSV infected and immuzone treated condition, immune genes were inducible in all tissues when compared to its untreated condition. The expression levels of Hsp21, Hsp70 and Hsp90 were determined by quantitative real-time PCR in four tissues (gill, hepatopancreas, pleopod and muscle) of Litopenaeus vannamei in WSSV treated and normal shrimps. Under untreated condition, all three Hsp genes were differentially expressed in all of the examined tissues. Under WSSV infected condition, only Hsp70 was inducible in all tissues when compared to its untreated condition. The time course induction experiment in gill, muscle, pleopod and hepatopancreas revealed that the transcriptional level of Hsp70 was induced and that Hsp21 and Hsp90 were uninducible under the WSSV treated condition. The expression level of Hsp70 was significantly increased after a 24, 48-h exposure to WSSV whereas the Hsp21 and Hsp90 transcripts were down regulated later after WSSV exposure. This evidence suggests that there is a putative role and involvement of the Hsp genes as a part of immunity response against WSSV in Litopenaeus vannamei.