The Cloning Of A Heat Shock Protein 90 Beta Gene And Expression Analysis In Botia Reevesae After Ammonia-N Exposure And Aeromonas Hydrophila Challenge

The objective of this study was to clone the full-length cDNA of Heat shock protein 90 (HSP90) in Botia reevesae and to determine the effects of pathogenic bacterial challenge after acute sublethal ammonia exposure on HSP90 beta expression. The HSP90 beta cDNA of B. reevesae contained 2358 bp, including a 1947 bp open reading frame, a 36 bp 5'-untranslated region (UTR), a 375 bp 3'-UTR. Sequence comparisons indicated that the predicted amino acid sequence of B. reevesae HSP90 showed a high degree of similarity with other known HSP90 beta genes, and contained five HSP superfamily signatures, thus suggesting that B. reevesae HSP90 beta is a cytosolic member of the HSP90 family. Quantitative real-time PCR analysis revealed that HSP90 transcripts could be detected in all of the tissues tested, and was strongly expressed in liver, gill and kidney tissues (p<0.05) of B. reevesae after sublethal ammonia-N exposure and Aeromonas hydrophila challenge. Additionally, following sublethal ammonia-N exposure and A. hydrophila challenge, expression of HSP90 beta mRNA transcripts was increased in gill and kidney tissues by 6-24 h (p<0.05), and was more reduced in the liver than the levels observed in response to ammonia-N exposure or A. hydrophila challenge alone. This result indicated that after ammonia-N stress, B. reevesae could trigger elevated HSP90 beta expression in specific tissues to respond to pathogenic bacteria. C) 2016 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.