A procedure for extracting and separating plant proteins by isoelectric point and 2-dimensional gel electrophoresis (2-DGE) is presented. Resolution of basic proteins using nonequilibrium pH gradient electrophoresis (NEPHGE) increased when run without the presence of acidic proteins. Isoelectric focusing without basic proteins favored the migration of the acidic and the more neutrally charged proteins into tube gels. Without the basic groups, negatively charged proteins could be focused for 20 h and longer without consideration of cathodic drift effects. The procedure facilitates gel analysis by simplifying the protein pattern on second dimension gels. Another advantage is that greater relative amounts of any class of proteins can be electrophoresed in the first dimension gels.