title: Molecular cloning, characterization and expression of heat shock protein 90 gene in the haemocytes of bay scallop Argopecten irradians.
abstract: Heat shock protein 90 (HSP90) is a highly conserved molecular chaperone that plays key roles in the folding, maintenance of structural integrity and regulation of a subset of cytosolic proteins. In the present study, the cDNA of Argopecten irradians HSP90 (designated AiHSP90) was cloned by the combination of homology cloning and rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of AiHSP90 was of 2669 bp, including an open reading frame (ORF) of 2175 bp encoding a polypeptide of 724 amino acids with predicted molecular weight of 83.08 kDa and theoretical isoelectric point of 4.81. BLAST analysis revealed that AiHSP90 shared high similarity with other known HSP90s, and the five conserved amino acid blocks defined as HSP90 protein family signatures were also identified in AiHSP90, which indicated that AiHSP90 should be a cytosolic member of the HSP90 family. Fluorescent real-time quantitative PCR was employed to examine the expression pattern of AiHSP90 mRNA in haemocytes of scallops challenged by Gram-negative bacteria Vibrio anguillarum and Gram-positive bacteria Micrococcus luteus. In both bacterial challenged groups, the relative expression level of AiHSP90 transcript was up-regulated and reached maximal level at 9h after injection, and then dropped progressively to the original level at about 48 h post challenge. The results indicated that AiHSP90 was potentially involved in the immune responses against bacteria challenge in scallop A. irradian.
authors.affiliation: Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Gao
authors.forename: Jianmin
authors.initials: J
authors.lastname: Zhao
authors.forename: Linsheng
authors.initials: L
authors.lastname: Song
authors.forename: Limei
authors.initials: L
authors.lastname: Qiu
authors.forename: Yundong
authors.initials: Y
authors.lastname: Yu
authors.forename: Huan
authors.initials: H
authors.lastname: Zhang
authors.forename: Duojiao
authors.initials: D
authors.lastname: Ni
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics*; D006434:Hemocytes / Q000378:metabolism*; D008969:Molecular Sequence Data; D049897:Pectinidae / Q000235:genetics* / Q000276:immunology; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D014733:Vibrio / Q000276:immunology
chemical_list: D018076:DNA, Complementary; D018841:HSP90 Heat-Shock Proteins