Molecular cloning and expression analysis of two β-defensin genes in the blunt snout bream (Megalobrama amblycephala)
- Authors
- Liang, T., Wang, D.D., Zhang, G.R., Wei, K.J., Wang, W.M., and Zou, G.W.
- ID
- ZDB-PUB-130806-1
- Date
- 2013
- Source
- Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology 166(1): 91-8 (Journal)
- Registered Authors
- Keywords
- antimicrobial peptide, β-Defensins, Megalobrama amblycephala, gene expression, bacterial stimulation
- MeSH Terms
-
- Aeromonas/immunology
- Aeromonas/pathogenicity
- Amino Acid Sequence
- Animals
- Base Sequence
- Cloning, Molecular
- Cyprinidae/genetics*
- Cyprinidae/microbiology
- DNA, Complementary/genetics
- Gene Expression Regulation*
- Phylogeny
- Tissue Distribution
- Zebrafish/genetics
- beta-Defensins/biosynthesis
- beta-Defensins/genetics*
- beta-Defensins/immunology
- PubMed
- 23876385 Full text @ Comp. Biochem. Physiol. B Biochem. Mol. Biol.
β-Defensins are a group of cysteine-rich, cationic antimicrobial peptides that play important roles in innate immune system against pathogenic microbes invading. In this study, the part-length cDNA sequences of two β-defensin genes (maBD-1, maBD-2) in blunt snout bream (Megalobrama amblycephala) were identified. Homology analysis showed that the cDNA sequences of maBD-1 and ma’BD-2 had high similarities to those in common carp and zebrafish. Real-time quantitative PCR results exhibited that expression level of maBD-1 in juvenile tissues was the highest in skin, followed by blood and liver, whereas maBD-2 was lowly expressed in liver, kidney, brain and foregut. In the early development period, fertilized eggs to 31-day post-hatching (dph) larvae, the expression levels of maBD-1 were higher at the stage from heart beat stage to 3 dph with the highest value at 1 dph, whereas maBD-2 was expressed higher at fertilized eggs and late cleavage stages. Following bacterial stimulation in vivo by Aeromonas sobria, maBD-2 expressions were significantly up-regulated in liver, skin, gill, and foregut of juveniles, and maBD-1 expressions were significantly up-regulated in liver and skin. The results suggest that maBD-1 and maBD-2 may play important roles in protecting blunt snout bream embryos, fry and juveniles from pathogenic microbe invading.