Purification and biochemical characterization of a vitellogenin-like protein from sea urchin

• Published in: Fisheries science Vol. 85; no. 1; pp. 127 - 135
• Main Authors: Nishimiya, Osamu, Teraoka, Yoshihiko, Gotoh, Takahiro, Yuhi, Tomoharu, Higuchi, Ichiro, Ura, Kazuhiro, Takagi, Yasuaki
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Japan 01.01.2019; Springer Nature B.V
• Subjects: Affinity chromatography; Ammonium; Ammonium compounds; Ammonium sulfate; Anion exchange; Anion exchanging; Anions; Biomedical and Life Sciences; Chromatography; Echinoidea; Egg yolk; Eggs; Fish & Wildlife Biology & Management; Food Science; Fractionation; Freshwater & Marine Ecology; Gametogenesis; Gel electrophoresis; Gel filtration; Gels; Gonads; Life Sciences; Marine invertebrates; Mass spectrometry; Mass spectroscopy; Original Article; Ovaries; Physiological functions; Protein purification; Proteins; Sea urchins; Sodium lauryl sulfate; Transferrin; Transferrin-like protein; Transferrins; Vitellogenin; Water purification; Yolk; Yolk protein; Egg; Yolk protein; Large lipid transfer protein superfamily
• ISSN: 0919-9268; 1444-2906
• DOI: 10.1007/s12562-018-1273-7

The major yolk protein in sea urchins is a transferrin-like protein. In this report, a new component was detected in gonad extracts of Strongylocentrotus intermedius and Mesocentrotus nudus , which cross-reacts with antiserum against egg yolk proteins. We tentatively named them egg yolk-related proteins siYRP and mnYRP. The siYRP was purified from testis of S. intermedius by ammonium sulfate fractionation, anion exchange chromatography, affinity chromatography and gel filtration. Purified siYRP was > 900 kDa in size. The siYRP purified on SDS-PAGE under reducing conditions gave seven bands, corresponding to 93, 213 and > 250 kDa. Purified mnYRP displayed similar structural characteristics as siYRP. Purified siYRP and mnYRP were identified by tandem mass spectrometry and renamed as siVitellogenin (Vtg)-like and mnVtg-like proteins, respectively. Both Vtg-like proteins were confirmed to be lipoglycoproteins by staining with Sudan black and periodic acid-Schiff. A specific antiserum against the siVtg-like protein was raised in rabbit. Antiserum against the siVtg-like protein immunostained siVtg-like and mnVtg-like proteins. Immunochemical methods using the antiserum revealed that siVtg-like and mnVtg-like proteins were present in the ovary, testis and unfertilized eggs of both species. These results indicated that Vtg-like proteins have important physiological functions for gonadal growth and gametogenesis in sea urchins.