Immune-related genes in hemocytes of the black tiger shrimp, Penaeus monodon, infected with Vibrio harveyi

Abstract

A cDNA library was constructed from hemocytes of the black tiger shrimp Penaeus monodon that were infected with the luminous bacteria, Vibrio harveyi, to survey the immune-related genes which are induced and expressed in hemocytes. Four hundred and nine cDNA clones were sequenced and subjected to homology searches in the DNA databases. One hundred and eighty one clones (44%) showed significant homology to known genes but the remaining sequence (56%) did not match to any sequence in the GenBank. Forty one clones (10%) were identified as putative immune-related genes and represented 14 different immune genes. Antimicrobial peptides were the most common group of immune-related ESTs found in infected hemocytes. The ESTs coding for putative anti-lipopolysaccharide factor (16 clones) and 11.5 kDa antibacterial protein (8 clones) were predominate among the immune genes indicating the high abundance of these transcripts in infected hemocytes. High expression of these antimicrobial proteins suggests that they play a major role in the host respose to V. harveyi infection. © 2002, The Japanese Society of Fisheries Science. All rights reserved.