Biogenesis of the platelet receptor for fibrinogen: evidence for separate precursors for glycoproteins IIb and IIIa

Journal Article · Sat Mar 01 00:00:00 EST 1986 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.83.5.1480· OSTI ID:5622335

Bray, P F; Rosa, J P; Lingappa, V R; Kan, Y W; McEver, R P; Shuman, M A

Congenital absence of platelet glycoproteins IIb and IIIa (GPIIb and GPIIIa) results in a severe bleeding disorder characterized by defective platelet aggregation and failure of fibrinogen to bind to platelets. GPIIb is a two-chain protein containing disulfide-linked ..cap alpha.. and ..beta.. subunits. GPIIb and GPIIIa are present as a heterodimeric, noncovalent complex in the platelet plasma membrane and function as the fibrinogen receptor. To characterize synthesis of these two proteins, RNA isolated from a human leukemia cell line that contains GPIIb and GPIIIa was translated in a wheat germ cell-free system. Polyclonal antibodies specific for each protein immunoprecipitated distinct (/sup 35/S)methionine-labeled precursors, indicating that GPIIb and GPIIIa are translated from separate mRNAs. Moreover, using specific antibodies against either intact unreduced GPIIb or the ..beta.. subunit, the authors obtained evidence for synthesis of a common polypeptide precursor for GPIIb..cap alpha.. and GPIIb..gamma... Based on experiments using microsomal membranes, it appears that GPIIb is integrated into the platelet membrane with little or no cytoplasmic component. These results suggest that precursors of GPIIb and GPIIIa may be encoded by separate genes and that each precursor is processed before delivery to the plasma membrane.

• Research Organization: Univ. of California Medical Center, San Francisco
• OSTI ID: 5622335
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Vol. 83:5, Issue 5
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BLOOD PLATELETS
LABELLING
GLUCOPROTEINS
BIOSYNTHESIS
LABELLED COMPOUNDS
FIBRINOGEN
LEUKEMIA
MAN
MESSENGER-RNA
METHIONINE
RECEPTORS
SULFUR 35
TUMOR CELLS
AMINO ACIDS
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BLOOD COAGULATION FACTORS
BODY FLUIDS
CARBOHYDRATES
CARBOXYLIC ACIDS
COAGULANTS
DAYS LIVING RADIOISOTOPES
DISEASES
DRUGS
EVEN-ODD NUCLEI
GLOBULINS
HEMATOLOGIC AGENTS
HEMIC DISEASES
HEMOSTATICS
ISOTOPES
LIGHT NUCLEI
LIPOTROPIC FACTORS
MAMMALS
MATERIALS
MEMBRANE PROTEINS
NEOPLASMS
NUCLEI
NUCLEIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PRIMATES
PROTEINS
RADIOISOTOPES
RNA
SACCHARIDES
SULFUR ISOTOPES
SYNTHESIS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques