Purification and Characterization of a Yolk Protein from the Scallop Ovary.

Abstract

A female specific protein (FSP) was identified and purified from the ovary of the Japanese scallop Patinopecten yessoensis by immunological techniques and a combination of precipitation with distilled water, ammonium sulfate fractionation, hydroxylapatite chromatography, and gel filtration. The molecular mass was determined to be approximately 450kDa. Three other female specific proteins, two with the same molecular mass and the other with 700kDa, showed different electrophoretic mobility from each other on native polyacrylamide gel electrophoresis, and reacted to antiserum against purified FSP (anti-FSP) by immunoblotting. No FSP was immunologically detected in the extract of the digestive diverticula or in the concentrated hemolymph. However, the extracts from the ovary of Chlamys farreri nipponensis and Mytilus edulis, though not those of Crassostrea gigas, reacted to anti-FSP. The amount of FSP in the ovarian extract from the scallop increased with the progressive growth of the oocytes and this protein wsa localized in the cytoplasm of the oocyte. It is assumed that the purified FSP is formed as a yolk protein in the ovary and the yolk protein is possibly composed of four molecules synthesized from the same source as this purified FSP, the antigenicity of which is partially maintained among bivalve species.

Études de biomarqueurs chez la mye commune (Mya arenaria) du fjord du Saguenay : bilan de recherches (1997 à 2006)

“…Les Vg sont des protéines de haut poids moléculaire (>400 kda) constituées d'hydrates de carbone, de lipides, de phosphates labiles en milieu alcalin dites alkali labile phosphates, de calcium et de zinc que l'on retrouve dans les tissus de gonades de bivalves (OSADA et al, 1992;SUZUKI et al, 1992). En juin 1998, nous avons récolté des myes provenant du site de référence ASE et des sites BE et ASJ (voir Figure 1 et Tableau 1 pour leur emplacement et caractéristiques pollutionnelles), afin de tester l'hypothèse selon laquelle les niveaux des constituants de la Vg pourraient être altérés par la présence de contaminants.…”

Lipoproteins and heat shock proteins as measures of reproductive physiology in the soft shell clam, Mya arenaria

“…Osada et al (1992) and Suzuki et al (1992) suggested that the lipovitellin is synthesized within the oocytes. Recently, Lee et al (1996) The constitutive and inducible forms of hsp 70 appear to be functionally similar, with the induction of the heat shock response regulating the total pool of hsp 70 in the cell .…”

Immunohistochemical observations of vitellin synthesis and accumulation processes in ovary of Ezo abalone Haliotis discus hannai

“…yessoensis [1,3], but analysis of the Vtg gene expression by in situ hybridization has clarified it to occur in the ovarian follicle cells in C. gigas [7] and H. discus hannai [10], or auxiliary cells (equivalent to the ovarian follicle cells) in P. yessoensis [8].…”

“…Purification of the Vn revealed it to be a large molecule ranging from 700 kDa to 450 kDa in its native form and composed of several subunits [1,3,4]. The Vn is synthesized as a precursor molecule, vitellogenin (Vtg), and processed by proteases into a mature molecule.…”

“…Crassostrea gigas [1], Mexican Pacific oyster C. corteziensis [2], scallop Patinopecten yessoensis [3,4], Manila clam Ruditapes philippinarum [5], softshell clam Mya arenaria [6], and Ezo abalone Haliotis discus hannai [4]. Purification of the Vn revealed it to be a large molecule ranging from 700 kDa to 450 kDa in its native form and composed of several subunits [1,3,4].…”