title: Cloning and characterization of a hsp70 gene from Asiatic hard clam Meretrix meretrix which is involved in the immune response against bacterial infection.
abstract: In the present study, a 71.43 kDa heat shock protein cDNA was cloned from Asiatic hard clam Meretrix meretrix. The cDNA was 2292 bp, containing an open reading frame (ORF) of 1959 bp, which encodes a protein of 652 amino acids with a theoretical molecular weight of 71.43 kDa and an isoelectric point of 5.32. Based on the amino acid sequence analysis and phylogenetic analysis, this hsp70 cDNA is a member of cytoplasmic hsc70 (constitutive genes) subfamily in the hsp70 family, and is designated as MmeHsc71. Quantitative RT-PCR was carried out to compare the spatial and temporal expression patterns of MmeHsc71 in the mRNA level between control clams and Vibrio parahaemolyticus-infected clams. Spatially, MmeHsc71 mRNA was found in all tested tissues, including foot, hepatopancreas, mantle and gill. MmeHsc71 mRNA expression level in hepatopancreas and gill displayed a significant increase in vibrio-challenged clams at 24h post-infection compared to control clams (P < 0.05). Temporally, there was a significant increase of MmeHsc71 mRNA level in hepathopancreas of vibrio-challenged clams compared to control clams at 6, 12, and 24h post-challenge, respectively. The result of quantitative immunofluorescence also indicated that there was obvious increase of MmeHsc71 in hepatopancreas of vibrio-challenged clams compared to control clams in protein level at 24h post-infection. The results suggested that MmeHsc71 may play an important role in mediating the immune responses of M. meretrix to bacterial challenge.
authors.affiliation: Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Yue
authors.forename: Baozhong
authors.initials: B
authors.lastname: Liu
authors.forename: Li
authors.initials: L
authors.lastname: Sun
authors.forename: Baojun
authors.initials: B
authors.lastname: Tang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D049872:Bivalvia / Q000145:classification / Q000235:genetics* / Q000276:immunology* / Q000382:microbiology; D003001:Cloning, Molecular; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics* / Q000276:immunology*; D043143:Hepatopancreas / Q000276:immunology / Q000473:pathology; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D014736:Vibrio parahaemolyticus / Q000502:physiology
chemical_list: D018840:HSP70 Heat-Shock Proteins