Structural and functional studies on the sodium- and chloride-coupled. gamma. -aminobutyric acid transporter: Deglycosylation and limited proteolysis

Journal Article · Tue May 02 04:00:00 EDT 1989 · Biochemistry; (USA)

DOI:https://doi.org/10.1021/bi00435a015· OSTI ID:5353817

Kanner, B I; Keynan, S; Radian, R ^[1]

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1. Hebrew Univ., Jerusalem (Israel)

The sodium- and chloride-coupled {gamma}-aminobutyric transporter, an 80-kDa glycoprotein, has been subjected to deglycosylation and limited proteolysis. The treatment of the 80-kDa band with endoglycosidase F results in its disappearance and reveals the presence of a polypeptide with an apparent molecular mass of about 60 kDa, which is devoid of {sup 125}I-labeled wheat germ agglutinin binding activity but is nevertheless recognized by the antibodies against the 80-kDa band. Upon limited proteolysis with papain or Pronase, the 80-kDa band was degraded to one with an apparent molecular mass of about 60 kDa. This polypeptide still contains the {sup 125}I-labeled wheat germ agglutinin binding activity but is not recognized by the antibody. The effect of proteolysis on function is examined. The transporter was purified by use of all steps except that for the lectin chromatography. After papain treatment and lectin chromatography, {gamma}-aminobutyric transport activity was eluted with N-acetylglucosamine. The characteristics of transport were the same as those of the pure transporter, but the preparation contained instead of the 80-kDa polypeptide two fragments of about 66 and 60 kDa. The ability of the anti-80-kDa antibody to recognize these fragments was relatively low. The observations indicate that the transporter contains exposed domains which are not important for function.

• OSTI ID: 5353817
• Journal Information: Biochemistry; (USA), Journal Name: Biochemistry; (USA) Vol. 28:9; ISSN 0006-2960; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALI METAL COMPOUNDS
AMINO ACIDS
AMINOBUTYRIC ACID
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BIOELECTRICITY
BODY
BRAIN
CARBOXYLIC ACIDS
CENTRAL NERVOUS SYSTEM
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
DAYS LIVING RADIOISOTOPES
DECOMPOSITION
DRUGS
ELECTRICITY
ELECTRON CAPTURE RADIOISOTOPES
GLYCOPROTEINS
HALIDES
HALOGEN COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
MAMMALS
MEMBRANE PROTEINS
MEMBRANE TRANSPORT
MOLECULAR STRUCTURE
NERVOUS SYSTEM
NEUROREGULATORS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PROTEINS
PROTEOLYSIS
RADIOISOTOPES
RATS
RODENTS
SODIUM CHLORIDES
SODIUM COMPOUNDS
VERTEBRATES