Document Type

Article

Department/Program

Virginia Institute of Marine Science

Publication Date

2008

Journal

Comparative Biochemistry And Physiology D-Genomics & Proteomics

Volume

3

Issue

4

First Page

263

Last Page

269

Abstract

Two partial mRNA sequences predicted to encode anti-lipopolysaccharide factors (ALFs) were identified among expressed sequence tags generated from the American lobster Homarus americanus and complete cDNA sequences were obtained from library clones. Comparison of the translated amino acid sequences to those publicly available confirmed similarity to arthropod anti-lipopolysaccharide factors. Both protein sequences, designated ALFHa-1 and ALFHa-2, contained an N-terminal signal peptide and two half-cysteines participating in a disulfide bridge, features conserved in other ALFs. Predicted secondary structures were similar to that described for the ALF from the horseshoe crab Limulus polyphemus. As part of an exploratory study of immunity in H. americanus, lobsters were injected with the bacterium Vibrio fluvialis and gill, hematopoietic, and hepatopancreas tissues were sampled for analysis of gene expression of ALFHa-1 and ALFHa-2 by quantitative PCR. The relative abundance of ALFHa-2 mRNA was not significantly affected by Vibrio injection in any of the three tissues tested. In contrast, ALFHa-1 mRNA levels in gills were increased by the treatment some 17-fold. Our results support a molecularly specific regulation of antimicrobial proteins in response to bacterial infection in H. americanus. (C) 2008 Elsevier Inc. Ail rights reserved.

DOI

10.1016/j.cbd.2008.07.001

Keywords

Shrimp Penaeus-Monodon; Black Tiger Shrimp; Horseshoe-Crab; Antimicrobial Activity; Litopenaeus-Vannamei; Gene Discovery; Factor Alf; Protein; Expression; Hemocytes

Share

COinS