Diversity, structure, and expression of the gene for p26, a small heat shock protein from Artemia.
p26, a small heat shock protein, is thought to protect Artemia embryos from stress during encystment and diapause. Full-length p26 cDNAs were compared and used to determine phylogenetic relationships between several Artemia species. The alpha-crystallin domain of p26 was the most conserved region of the protein and p26 from each Artemia species contained characteristic amino-terminal WD/EPF and carboxy-terminal VPI motifs. Sequence conservation suggested the importance of p26 to oviparously developing Artemia embryos and indicated common functions for the protein during development and stress resistance, although as shown by modeling some species-specific p26 amino acid substitutions may have adaptive significance. The p26 gene obtained from A. franciscana exhibited a unique sHSP intron arrangement with an intron in the 5'-untranslated region. Computer-assisted analysis revealed heat shock elements and other putative cis regulatory sequences but their role in gene regulation is unknown. In contrast to previous results for which Northern blots were analyzed, p26 gene expression was observed in ovoviviparous embryos by use of PCR-based methodology, but the p26 protein was not detected.
Department of Biology, Dalhousie University, Halifax, Canada NS B3H 4J1.
Zhijun
Z
Qiu
Peter
P
Bossier
Xiaomei
X
Wang
Svetla
S
Bojikova-Fournier
Thomas H
TH
MacRae
D000595:Amino Acid Sequence; D000818:Animals; D001156:Artemia / Q000235:genetics*; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006360:Heat-Shock Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D050888:Heat-Shock Proteins, Small / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D008297:Male; D018832:Molecular Chaperones / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
D018076:DNA, Complementary; D006360:Heat-Shock Proteins; D050888:Heat-Shock Proteins, Small; D018832:Molecular Chaperones; C107632:p26 chaperone protein, Artemia franciscana