Two-dimensional maps in soft immobilized pH gradient gels: a new approach to the proteome of the Third Millennium.
Same major improvements in proteome analysis of cytosolic and membrane proteins by two-dimensional mapping are here reported. A much improved transfer of proteins from the first to the second dimensional sodium dodecyl sulfate (SDS)-gel is obtained by simply diluting the gel matrix, normally composed of 4%T polyacrylamide in all commercially available Immobiline strips down to as low as 3%T. In the analysis of total lysates of platelets, this augmented transfer has been evaluated as being 2-3 times higher than in standard 4%T gels. A second major improvement, in the case of analysis of membrane protein preparations, has been demonstrated to consist in a delipidation step in a tertiary solvent mixture composed of tri-n-butyl phosphate:acetone:methanol in a 1:12:1 ratio. By adopting this protocol, large amounts of spectrins (240-220 kDa, filamentous proteins of the red blood cell membranes) could be transferred vs. essentially none when delipidation was omitted. The present report also confirms the importance of a reduction and alkylation step of the protein sample prior to all electrophoretic steps, including focusing in the Immobiline gel, as recently reported by Herbert et al.
Candiano
Giovanni
G
Nephrology Section, G. Gaslini Children's Hospital, Genova, Italy.
Musante
Luca
L
Bruschi
Maurizio
M
Ghiggeri
Gian Marco
GM
Herbert
Ben
B
Antonucci
Francesca
F
Righetti
Pier Giorgio
PG
D000180:Acrylic Resins; D001792:Blood Platelets / Q000737:chemistry; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D004910:Erythrocyte Membrane / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008565:Membrane Proteins / Q000032:analysis*; D010449:Peptide Mapping / Q000379:methods; D020543:Proteome / Q000032:analysis*
D000180:Acrylic Resins; D008565:Membrane Proteins; D020543:Proteome; C016680:polyacrylamide gels