The cytosolic G‐protein α‐subunit in human neutrophils responds to treatment with guanine nucleotides and magnesium

FEBS Letters

Schultz, Günter¹  Rosenthal, Walter¹  Rudolph, Uwe¹ 

[1] Institut für Pharmakologie der Freien Universität Berlin, Thielallee 69-73, D-1000 Berlin 33, Germany

关键词: Signal transduction;    Guanine nucleotide binding regulatory protein;    Guanine nucleotide;    Neutrophil;    Cytosol;    GTPγS;    guanosine 5′-O-(3-thiotriphosphate);    GMP-P(NH)P;    guanyl-5′-yl imidodiphosphate;    SDS-PAGE;    SDS-polyacrylamide gel electrophoresis;    pertussis toxin (islet-activating protein);    main exotoxin of Bordetella pertussis;    S 20.w;    standard sedimentation coefficient in water at 20°C;   

DOI  :  10.1016/0014-5793(89)81443-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The hydrodynamic properties of the G_i2 α-subunit in human neutrophil cytosol were analyzed. The s _20,w value was 3.3 S at 30°C and 4.1 S at 4°C. Reconstitution of the cytosolic α-subunit with βγ-complex purified from porcine brain resulted in an s _20,w value of 4.0 S at 30°C and 4.2 S at 4°C. Treatment of cytosol with G-protein-activating agents, GTPγS and MgCl₂, decreased the s _20,w value to 2.4 S at 30°C and 2.9 S at 4°C. Our results indicate that the cytosolic α-subunit of neutrophils is an inactive monomeric species at 30°C capable of interacting with G-protein βγ-complex and responsive to treatment with activating agents leading to the two activated forms, α* at 4°C and α** at 30°C.

【 授权许可】

Unknown