title: Anomalous electrophoretic behavior of a very acidic protein: ribonuclease U2.
abstract: Ribonuclease U2 is a low-molecular-weight acidic protein with three disulfide bridges. This protein displays an anomalous electrophoretic behavior on standard SDS-PAGE. The electrophoretic mobility of the nonreduced protein roughly corresponds to its molecular mass while the migration of the reduced protein would be in accordance with the expected molecular mass of the protein dimer. This study reveals that the protein does not bind SDS under the SDS-PAGE conditions, its electrophoretic mobility being only determined by its electrostatic charge and hydrodynamic properties. In addition, the nonreduced protein cannot be blotted to a membrane. Unfolding of the protein upon reduction of its disulfide bridges enables electrotransference to membranes due to a restricted diffusion along the electrophoresis gel.
authors.affiliation: Departamento de Bioquímica y Biología Molecular I, Facultad de Química, Universidad Complutense, Madrid, Spain.
authors.forename: Lucía
authors.initials: L
authors.lastname: García-Ortega
authors.forename: Vivian
authors.initials: V
authors.lastname: De los Ríos
authors.forename: Antonio
authors.initials: A
authors.lastname: Martínez-Ruiz
authors.forename: Mercedes
authors.initials: M
authors.lastname: Oñaderra
authors.forename: Javier
authors.initials: J
authors.lastname: Lacadena
authors.forename: Alvaro
authors.initials: A
authors.lastname: Martínez del Pozo
authors.forename: José G
authors.initials: JG
authors.lastname: Gavilanes
mesh_terms: D000595:Amino Acid Sequence; D015153:Blotting, Western; D002942:Circular Dichroism; D004220:Disulfides / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D004722:Endoribonucleases / Q000737:chemistry / Q000302:isolation & purification*; D006358:Hot Temperature; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010720:Phosphines / Q000737:chemistry; D011485:Protein Binding; D011489:Protein Denaturation; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry
chemical_list: D004220:Disulfides; D004722:Endoribonucleases; D010720:Phosphines; D012967:Sodium Dodecyl Sulfate; C080938:tris(2-carboxyethyl)phosphine; C022544:ribonuclease U2