Characterization of Yolk Proteins in the Freshwater Crab Travancoriana schirnerae
Characterization of Yolk Proteins in the Freshwater Crab Travancoriana schirnerae
Date
2015
Authors
Smija, M.K
Devi, A. R. Sudha
Journal Title
Journal ISSN
Volume Title
Publisher
Society of Fisheries Technologists (India)Cochin
Abstract
Vitellogenesis, the most important part of the
reproductive process, involves the synthesis of yolk
proteins and their deposition in oocytes. The objective
of this study was to characterize yolk proteins
of the freshwater crab Travancoriana schirnerae using
sodium dodecyl sulphate-polyacrylamide gel electrophoresis.
The results revealed that the hemolymph
yolk protein, vitellogenin is composed of two high
molecular weight polypeptide subunits 153.53 and
166.73 kDa. The ovarian yolk protein, vitellin is
composed of four polypeptide subunits with molecular
weights 60.25, 69.25, 82.68 and 115 kDa. The
high molecular weight vitellin polypeptides, 82.68
and 115 kDa appeared in early primary vitellogenic
ovary. The vitellin fraction of late primary and
secondary vitellogenic ovaries contained a low
molecular weight subunit, 69.25 kDa besides the
82.68 and 115 kDa fractions. All the four polypeptide
fractions were detected in the tertiary vitellogenic
ovary and freshly oviposited eggs. Vitellin polypeptides
were not demonstrated in previtellogenic or
spent ovaries. Biochemical analyses revealed that
vitellin is a lipoglycoprotein as it is stainable with
Sudan Black B and periodic acid Schiff’s reagent. It
was concluded that the two vitellogenin subunits
may possibly undergo proteolytic cleavage to give
rise to four vitellin subunits of the ovary.
Description
Keywords
Hemolymph, ovary, Travancoriana schirnerae, vitellin, vitellogenin
Citation
Fishery Tech 52(1):13-19