title: Biochemical and immunological relationships among fibronectin-like proteins from different sea urchin species.
abstract: Fibronectin-like proteins were purified from ovaries of the sea urchin species, Paracentrotus lividus (PI), Sphaerechinus granularis (Sg), Arbacia lixula (Al), Pseudocentrotus depressus (Pd), and Anthocidaris crassispina (Ac), by gelatin-Sepharose affinity chromatography. The major component had a molecular mass of 180 kDa and was eluted by 1 M NaCl or 8 M urea, depending on the species used. By substrate adhesion assay, we tested the biological activity of the 180 kDa protein purified from Paracentrotus lividus (P1-180K) and showed that it promotes the adhesion of homologous embryonic cells to the substrate. An antiserum, developed against Temnopleurus hardwickii fibronectin-like protein (Th-180K), was used in Western blots of the proteins purified from the five species. The antibody cross-reacted with Pl-180K, Pd-180K and Ac-180K. A peptide map of P1-180K, obtained by V8 protease partial digestion, was compared with those obtained from the other four proteins and showed an homology between 40 and 56%. This report confirms that fibronectin-like proteins can be purified from sea urchins on the basis of their binding to gelatin-Sepharose; the proteins differ for their binding affinity to gelatin and share different epitopes, suggesting that they are members of a sea urchin fibronectin super family.
authors.affiliation: Istituto di Biologia dello Sviluppo del Consiglio Nazionale delle Ricerche, Via Archirafi 20 I-90123, Palermo, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Matranga
authors.affiliation: Istituto di Biologia dello Sviluppo del Consiglio Nazionale delle Ricerche, Via Archirafi 20 I-90123, Palermo, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Zito
authors.affiliation: Istituto di Biologia dello Sviluppo del Consiglio Nazionale delle Ricerche, Via Archirafi 20 I-90123, Palermo, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Tesoro
authors.affiliation: Biological Laboratory, Aichi Prefectural University, 467, Mizuho, Nagoya, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yokota
authors.affiliation: Nagoya University, 464, Chikusa, Nagoya, Japan.
authors.forename: E
authors.initials: E
authors.lastname: Nakano
keywords: Cell-substrate adhesion; Fibronectin-like proteins Peptide mapping; Sea urchin