TMHMM-based interstudy comparison and membrane protein enrichment. (A) Prediction of membrane spanning proteins was done by TMHMM 2.0; comparison with several published studies on the platelet proteome clearly shows an increased number of identified membrane proteins by the current approach. (B) CBB-G250–stained 1D-SDS-PAGE of whole platelet lysates and enriched plasma membranes by aqueous 2-phase partitioning (* indicates gpIIb/IIIa; #, actin; proteins were identified by mass spectrometric sequencing).