Synthesis and phosphorylation of the glial fibrillary acidic protein during brain development: A tissue slice study

Journal Article · Mon Jan 01 00:00:00 EST 1990 · Glia (New York); (USA)

DOI:https://doi.org/10.1002/glia.440030603· OSTI ID:6214582

Noetzel, M J ^[1]

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1. Washington Univ. School of Medicine, St. Louis, MO (USA)

Brain slices were incubated with either (3H) amino acids or (32P) orthophosphate in order to characterize the synthesis and phosphorylation of the glial fibrillary acidic protein (GFAP) in the rat nervous system. The incorporation of (3H) amino acids into GFAP was found to increase significantly during early postnatal development, reaching a peak of activity on day 5 of life and then declining over the next 2 weeks. Concomitant with this peak of synthetic activity the content of GFAP in rat brain was also observed to increase dramatically. GFAP continued to accumulate in brain through postnatal day 30 despite a decrease in the synthesis of the protein. These results indicate that the increase in GFAP during the first month of life cannot be ascribed solely to the rate of GFAP synthesis. The findings are consistent with the hypothesis that during later stages of astrocytic development the accumulation of GFAP may be primarily dependent upon a low rate of protein degradation. The pattern of GFAP phosphorylation in the developing rat brain differed from that observed for the incorporation of (3H) amino acids. The peak incorporation of 32P into GFAP occurred on postnatal day 10 at a time when synthesis of the protein had declined by 43%. These findings suggest that during development phosphorylation of GFAP is mediated by factors different from those directing its synthesis. In addition, phosphorylation of GFAP did not alter its solubility in cytoskeletal preparations indicating that GFAP phosphorylation is probably not a major regulatory mechanism in disassembly of the astroglial filaments.

• OSTI ID: 6214582
• Journal Information: Glia (New York); (USA), Vol. 3:6; ISSN 0894-1491
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
PHOSPHOPROTEINS
POST-TRANSLATION MODIFICATION
AMINO ACIDS
BIOSYNTHESIS
BRAIN
MICROTUBULES
NERVE CELLS
NERVOUS SYSTEM
PHOSPHATES
PHOSPHORUS 32
PHOSPHORYLATION
RATS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CENTRAL NERVOUS SYSTEM
CHEMICAL REACTIONS
DAYS LIVING RADIOISOTOPES
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MAMMALS
NUCLEI
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
OXYGEN COMPOUNDS
PHOSPHORUS COMPOUNDS
PHOSPHORUS ISOTOPES
PROTEINS
RADIOISOTOPES
RODENTS
SOMATIC CELLS
SYNTHESIS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques