[Identification and purification of GTP-binding regulatory proteins from plasma membranes of swine heart].
A 23 kDa GTP-binding protein was purified from pig heart sarcolemma. This protein was not ADP-ribosylated by cholera, pertussis and botulinum C3 toxins. In pig heart sarcolemma pertussis toxin ADP-ribosylated 40 kDa subunit of Gi-protein, cholera toxin--45 kDa subunit of Gs-protein, botulinum C3 toxin ADP-ribosylated a group of proteins with Mr 22, 26 and 29 kDa. Antiserum generated against the peptide common for all alpha-subunits of G-proteins did not react with purified 23 kDa protein. Trypsin cleaved the 23 kDa protein in the presence of guanyl nucleotides into a 22 kDa fragment. Proteolysis of the 39 kDa alpha 0-subunit from bovine brain plasma membranes and ADP-ribosylated 40 kDa alpha i-subunit from pig heart sarcolemma in the presence of GTP gamma S yielded the 37 and 38 kDa fragments, respectively. In the presence of GTP and GDP the proteolysis of alpha 0 yielded the 24 and 15 kDa fragments, while the proteolysis of ADP-ribosylated alpha i-subunit yielded a labelled 16 kDa peptide. Irrespective of nucleotides trypsin cleaved the ADP-ribosylated 26 kDa substrate of botulinum C3 toxin into two labelled peptides with Mr 24 and 17 kDa. The data obtained indicate the existence in pig heart sarcolemma of a new 23 kDa GTP-binding protein with partial homology to the alpha-subunits of "classical" G-proteins.
Goffenberg
S I
SI
Panchenko
M P
MP
Zhuravlev
I V
IV
Tkachuk
V A
VA
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D000818:Animals; D002462:Cell Membrane / Q000032:analysis; D019204:GTP-Binding Proteins / Q000302:isolation & purification*; D006868:Hydrolysis; D015151:Immunoblotting; D008970:Molecular Weight; D009206:Myocardium / Q000032:analysis*; D013379:Substrate Specificity; D013552:Swine
D000246:Adenosine Diphosphate Ribose; D019204:GTP-Binding Proteins
Identifikatsiia i ochistka GTP-sviazyvaiushchikh reguliatornykh belkov iz plazmaticheskikh membran serdtsa svin'i.