cDNA cloning and expression of grp94 in the Pacific oyster Crassostrea gigas

• Published in: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology Vol. 154; no. 3; pp. 290 - 297
• Main Authors: Kawabe, Shinya, Yokoyama, Yoshihiro
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01-11-2009
• Subjects: Air; Amino Acid Sequence; Animals; Cloning, Molecular; Crassostrea - cytology; Crassostrea - genetics; Crassostrea gigas; DNA, Complementary - genetics; Endoplasmic reticulum (ER); Gene Expression Regulation; GRP94; HSP70 Heat-Shock Proteins - chemistry; HSP70 Heat-Shock Proteins - genetics; Humans; Hypoxia; Marine; Membrane Proteins - chemistry; Membrane Proteins - genetics; Molecular chaperone; Molecular Sequence Data; Mollusca; Mollusk; Oyster; Phylogeny; RNA, Messenger - genetics; RNA, Messenger - metabolism; Strongylocentrotus purpuratus; Temperature; Xenopus laevis; Endoplasmic reticulum (ER); Mollusk; Oyster; Hypoxia; Crassostrea gigas; GRP94; Molecular chaperone
• ISSN: 1096-4959; 1879-1107
• DOI: 10.1016/j.cbpb.2009.07.001

The 94-kDa glucose-regulated protein (GRP94) is an endoplasmic reticulum (ER) chaperone. We cloned the first mollusk
grp94 from a cDNA library of the Pacific oyster
Crassostrea gigas. Analysis of
C. gigas grp94 (cg
grp94) clone containing 3212 bp DNA revealed that the cDNA contains a 2391 bp open reading frame that encodes a 797 amino acid protein of 91.6 kDa. The deduced amino acid sequence of cgGRP94 is 67%, 68%, and 67% homologous to the GRP94 of
Homo sapiens, GP96 of
Strongylocentrotus purpuratus, and GP96 of
Xenopus laevis, respectively. CgGRP94 contains an N-terminal 22 amino acid sequence, which is characteristic of a signal sequence. It also contains a HATPase_c domain. In addition, it contains the KDEL (-Lys-Asp-Glu-Leu) peptide motif at the C-terminus, which suggests that cgGRP94 localizes in the ER. Northern blot analysis showed that cg
grp94 mRNA is expressed at high levels in the gill which cg
grp94 mRNA is induced during air exposure condition. Expression patterns of cg
grp94 mRNA differed between gill and mantle, and cg
grp94 mRNA was induced at high temperature during air exposure condition. These indicate that cg
grp94 mRNA is induced by hypoxia and heat shock stress, and there are different strategies for air exposure condition between gill and mantle.