title: The polymorphism in the promoter of HSP70 gene is associated with heat tolerance of two congener endemic bay scallops (Argopecten irradians irradians and A. i. concentricus).
abstract: BACKGROUND
  The heat shock protein 70 (HSP70) is one kind of molecular chaperones, which plays a key role in protein metabolism under normal and stress conditions.
  
  
  METHODS
  In the present study, the mRNA expressions of HSP70 under normal physiological condition and after acute heat stress were investigated in gills of two bay scallop populations (Argopecten irradians irradians and A. i. concentricus). The heat resistant scallops A. i. concentricus showed significantly lower basal level and higher induction of HSP70 compared with that of the heat sensitive scallops A. i. irradians. The promoter sequence of HSP70 gene from bay scallop (AiHSP70) was cloned and the polymorphisms within this region were investigated to analyze their association with heat tolerance. Totally 11 single nucleotide polymorphisms (SNPs) were identified, and four of them (-967, -480, -408 and -83) were associated with heat tolerance after HWE analysis and association analysis. Based on the result of linkage disequilibrium analysis, the in vitro transcriptional activities of AiHSP70 promoters with different genotype were further determined, and the results showed that promoter from A. i. concentricus exhibited higher transcriptional activity than that from A. i. irradians (P<0.05).
  
  
  CONCLUSIONS
  The results provided insights into the molecular mechanisms underlying the thermal adaptation of different congener endemic bay scallops, which suggested that the increased heat tolerance of A. i. concentricus (compared with A. i. irradians) was associated with the higher expression of AiHSP70. Meanwhile, the -967 GG, -480 AA, -408 TT and -83 AG genotypes could be potential markers for scallop selection breeding with higher heat tolerance.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Chuanyan
authors.initials: C
authors.lastname: Yang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Qingdao Agricultural University, Qingdao, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; University of Chinese Academy of Sciences, Beijing, China.
authors.forename: Qiufen
authors.initials: Q
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Limei
authors.initials: L
authors.lastname: Qiu
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Linsheng
authors.initials: L
authors.lastname: Song
mesh_terms: D000220:Adaptation, Biological / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D002681:China; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000096:biosynthesis; D005786:Gene Expression Regulation / Q000235:genetics; D015723:Gene Library; D056726:Genetic Association Studies; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D006358:Hot Temperature; D008156:Luciferases; D008969:Molecular Sequence Data; D049897:Pectinidae / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; D018840:HSP70 Heat-Shock Proteins; D008156:Luciferases