title: Characterization of pregnancy-associated glycoproteins extracted from zebu (Bos indicus) placentas removed at different gestational periods.
abstract: In the present work, two biochemical approaches were used to characterize PAGs isolated from Bos indicus fetal cotyledons removed at different gestational ages. The first procedure included acidic and ammonium sulfate precipitations, anion and cation exchange chromatographies and the second included pepstatin-agarose affinity chromatography. A bovine PAG radioimmunoassay was used to monitor the immunoreactivity throughout the isolation procedures. The most immunoreactive fractions issued from cation exchange and affinity chromatographies were analyzed by SDS-PAGE and Western blotting, before transfer to a polyvinylidene difluoride (PVDF) membrane for NH2-microsequence determination. Use SDS-PAGE and Western blotting, different isoforms of PAG with apparent molecular masses of 51 to 69 kDa and isoelectric points varying from 4.4 to 6.7 were identified in the placentas from different gestational ages. N-terminal microsequencing (10 to 25 aa long) indicates the expression of one single terminal amino acid sequence in the Bos indicus placenta, which is 100% identical to the bovine PAG-1.
authors.affiliation: Faculty of Veterinary Medicine, Rural Sciences Center, Federal University of Santa Maria, Brazil.
authors.forename: Noelita Melo
authors.initials: NM
authors.lastname: Sousa
authors.forename: Benoit
authors.initials: B
authors.lastname: Remy
authors.forename: Bouchra
authors.initials: B
authors.lastname: El Amiri
authors.forename: José Ricardo
authors.initials: JR
authors.lastname: De Figueiredo
authors.forename: Henri
authors.initials: H
authors.lastname: Banga-Mboko
authors.forename: Paulo Bayard
authors.initials: PB
authors.lastname: Dias Gonçalves
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Beckers
mesh_terms: D000595:Amino Acid Sequence; D000645:Ammonium Sulfate; D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D002417:Cattle / Q000196:embryology / Q000502:physiology*; D011232:Chemical Precipitation; D002845:Chromatography / Q000662:veterinary; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D005260:Female; D005865:Gestational Age; D006023:Glycoproteins / Q000737:chemistry / Q000302:isolation & purification*; D008970:Molecular Weight; D010920:Placenta / Q000737:chemistry*; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000737:chemistry / Q000302:isolation & purification*; D020033:Protein Isoforms; D011863:Radioimmunoassay / Q000662:veterinary
chemical_list: D006023:Glycoproteins; D011257:Pregnancy Proteins; D020033:Protein Isoforms; D000645:Ammonium Sulfate