title: Cloning HSP70 and HSP90 genes of kaluga (Huso dauricus) and the effects of temperature and salinity stress on their gene expression.
abstract: The genes encoding HSP70 and HSP90 proteins were isolated from kaluga by homologous cloning and rapid amplification of complementary DNA (cDNA) ends (RACE). HSP70 (GenBank accession no. KP050541) and HSP90 (GenBank accession no. KP050542) cDNAs were composed of 2275 and 2718 bp and encoded polypeptides of 650 and 725 amino acids, respectively. Basic Local Alignment Search Tool (BLAST) analysis showed that HSP70 and HSP90 of kaluga shared high identities with those of Acipenser ruthenus, Acipenser schrenckii, and Acipenser baerii (98-99 %). Fluorescent real-time RT-PCR under unstressed conditions revealed that HSP70 and HSP90 were expressed in 11 different tissues of kaluga. Messenger RNA (mRNA) expressions of both HSP70 and HSP90 were highest in the intestine and lowest in the muscle. In addition, the patterns of mRNA expression of HSP70 and HSP90 were similar, although the level of expression was more in HSP90 than in HSP70 (P < 0.05).We also analyzed patterns of HSP70 and HSP90 expression in the muscle, gill, and liver of kaluga under different combinations of temperature and salinity stress, including temperatures of 4,10, 25, and 28 °C at 0 ppt salinity, and salinities of 10, 20, 30, and 40 ppt at 16 °C, where 16 °C at 0 ppt (parts per thousand) served as the control. We found that levels of mRNA expression of both HSP70 and HSP90 were highest at 4 °C in the muscle, gill, and liver and changed little with salinity stress. These results increase understanding of the mechanisms of stress response of cold freshwater fish.
authors.affiliation: College of Fisheries and Life Science, Dalian Ocean University, No.52 Heishijiao Street, Shahekou district, Dalian, 116023, Liaoning, People's Republic of China.
authors.forename: Guogan
authors.initials: G
authors.lastname: Peng
authors.affiliation: College of Fisheries and Life Science, Dalian Ocean University, No.52 Heishijiao Street, Shahekou district, Dalian, 116023, Liaoning, People's Republic of China. zhaowen_1963@163.com.
authors.forename: Wen
authors.initials: W
authors.lastname: Zhao
authors.affiliation: College of Fisheries and Life Science, Dalian Ocean University, No.52 Heishijiao Street, Shahekou district, Dalian, 116023, Liaoning, People's Republic of China.
authors.forename: Zhenguang
authors.initials: Z
authors.lastname: Shi
authors.affiliation: College of Fisheries and Life Science, Dalian Ocean University, No.52 Heishijiao Street, Shahekou district, Dalian, 116023, Liaoning, People's Republic of China.
authors.forename: Huirong
authors.initials: H
authors.lastname: Chen
authors.affiliation: College of Fisheries and Life Science, Dalian Ocean University, No.52 Heishijiao Street, Shahekou district, Dalian, 116023, Liaoning, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Fisheries and Life Science, Dalian Ocean University, No.52 Heishijiao Street, Shahekou district, Dalian, 116023, Liaoning, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Wei
authors.affiliation: College of Fisheries and Life Science, Dalian Ocean University, No.52 Heishijiao Street, Shahekou district, Dalian, 116023, Liaoning, People's Republic of China.
authors.forename: Fengying
authors.initials: F
authors.lastname: Gao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D003080:Cold Temperature; D058639:Cold-Shock Response; D029941:Fish Proteins / Q000032:analysis / Q000235:genetics*; D005399:Fishes / Q000235:genetics* / Q000502:physiology; D005786:Gene Expression Regulation; D018840:HSP70 Heat-Shock Proteins / Q000032:analysis / Q000235:genetics*; D018841:HSP90 Heat-Shock Proteins / Q000032:analysis / Q000235:genetics*; D010802:Phylogeny; D054712:Salinity; D013312:Stress, Physiological
chemical_list: D029941:Fish Proteins; D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins
keywords: Cloning and expression; HSP70; HSP90; Kaluga (Huso duricus); Salinity; Temperature