title: Comparisons of stress proteins and soluble carbohydrate in encysted embryos of Artemia franciscana and two species of Parartemia.
abstract: We compared stress proteins (p26, artemin, hsp70) and alcohol-soluble carbohydrates (ASC) in cysts of Artemia franciscana and two as yet un-named species populations of Parartemia, the brine shrimp endemic to Australia. The small stress proteins and molecular chaperones, p26 and artemin, previously thought to be restricted to Artemia, and present in very large amounts in its encysted embryos (cysts), were also detected by western blotting in Parartemia cysts, even though roughly 85-100 million years have passed since these genera diverged. We interpret this finding as further evidence for the adaptive importance of these proteins in coping with the severe stresses these encysted embryos endure. As expected, hsp70 was present in all three groups of cysts, but apparently at somewhat lower concentrations in those of Parartemia. Based on measurements of ASC we propose that the disaccharide trehalose, critical for desiccation tolerance in many animal cells, has probably also been maintained in the metabolic repertoire of Parartemia whose cysts have well developed tolerance to severe desiccation.
authors.affiliation: Bodega Marine Laboratory and Section of Molecular and Cellular Biology, University of California, Davis, Bodega Bay, CA 94923, USA. jsclegg@ucdavis.edu
authors.forename: James S
authors.initials: JS
authors.lastname: Clegg
authors.forename: Veronica
authors.initials: V
authors.lastname: Campagna
mesh_terms: D000818:Animals; D033202:Anostraca / Q000196:embryology* / Q000378:metabolism; D001156:Artemia / Q000196:embryology* / Q000378:metabolism; D060829:Arthropod Proteins; D002352:Carrier Proteins / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004625:Embryo, Nonmammalian / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism*; D033862:Iron-Binding Proteins; D018832:Molecular Chaperones / Q000378:metabolism; D016601:RNA-Binding Proteins; D012995:Solubility; D013045:Species Specificity; D014199:Trehalose / Q000378:metabolism*
chemical_list: D060829:Arthropod Proteins; D002352:Carrier Proteins; D006360:Heat-Shock Proteins; D033862:Iron-Binding Proteins; D018832:Molecular Chaperones; D016601:RNA-Binding Proteins; C490888:artemin protein, brine shrimp; C107632:p26 chaperone protein, Artemia franciscana; D014199:Trehalose