Abstract：The heat shock protein(HSP) is closely related with thermal-resistance of organisms. This study was conducted to investigate the expression of HSP90 mRNA in examined tissues from Shaoxing duck under the different treatments and during the recovery period after heat challenge, in hope of elucidating the molecular mechanism of HSP90 gene. HSP90 cDNA were cloned and characterized from the livers of Shaoxing duck (Anas platyrhyncho) using RT-PCR. The full-length of HSP90 consisted of an open reading frame of 2 211 bp encoding a putative protein of 736 amino acids (GenBank accession No. JQ837244). Comparison of amino acid sequence of HSP90 revealed that Shaoxing duck shared 92.6%~99% amino acid identity to that of domestic poultry and shared 80%~88% amino acid identity to that of some mammalian. Fluorescent Real-time quantitative PCR was applied to determined HSP90 expression after exposure to different thermal shock. Long-term treatment at 30℃ up-regulated HSP90 transcription in pituitary; long-term treatment at 35℃ significantly enhanced HSP90 expression in heart, liver and pituitary; acute treatment at 40℃ increased HSP90 level at maximum in heart, liver, kidney, pituitary and pancreas, respectively. During the recovery period, HSP90 mRNA in liver and heart reached their highest levels at 1 h post challenge and then both decreased to pre-challenge levels from 3 h post challenge. We concluded that levels of HSP90 mRNA in heart, liver and pituitary were significantly associated with the intensity of heat shock. The study provided basic data for the prevention and control of heat shock in Shaoxing duck using HSP90 mRNA expression as an index.
