There are a variety of approaches to identify groups of genes that change in expression in response to a particular stimulus
or environment. We here describe the application of suppression subtractive hybridization (SSH) for isolation and identification
genes in the brain of common carp (Cyprinus carpio) under cold temperatures. The materials were prepared through cooling the hybrid F2 of purse red carp (cold-tolerant strains)
and bighead carp (cold-sensitive species) to different regimes of temperatures. A subtracted cDNA library containing 2000
clones was constructed. About 60 positive clones were identified to express differentially by dot blotting in screening 480
clones. Sequencing 26 clones and aligning in GenBank/EMBL database using blastn searching engine, 15 genes showed higher similarities
with 85-98%. These annotated genes contained (1) genes for transcription factors and gene products involved in signal transduction
pathways such as zinc-finger protein, brevican; (2) genes involved in lipid metabolism such as Acyl-CoA synthetases, and (3)
genes involved in the translational machinery such as cytochrome c oxidase, ependymin glycoprotein. In addition, real-time
PCR was also conducted to validate these genes. To sum up, we believe this study will make an important contribution to elucidate
the possible mechanisms on fish cold tolerance at a molecular level.
Keywords cold tolerance - suppression subtractive hybridization (SSH) - real-time PCR - Cyprinus carpio