A UDP-glucose:glycoprotein glucose-1-phosphotransferase in embryonic chicken neural retina
A subclass of cell-surface glycoproteins from embryonic chicken neural retina contains a high mannose-type oligosaccharide that terminates with glucose linked via a phosphodiester bond to penultimate mannose. This unusual oligosaccharide seems responsible for the glycoprotein attachments to the cell-surface baseplate ligatin. Using beta-/sup 32/P-UDP-/sup 3/H-glucose, we demonstrate in retinal homogenates the existence of a UDP-glucose:glycoprotein glucose-1-phosphotransferase (GlcPTase) that catalyzes the synthesis of such a linkage. Characterization of the doubly labeled product resulting from activity of the transferase reveals a family of endoglycosidase H-sensitive oligosaccharides displaying a cation-exchange profile similar to that of oligosaccharides derived from ligatin-associated proteins synthesized in vivo. Further analysis confirms that the incorporation of label is due to a terminal /sup 3/H-glucose joined via a /sup 32/P-phosphodiester linkage to carbon 6 of a penultimate mannose. We propose that GlcPTase may be a controlling enzyme for the targeting of certain newly synthesized proteins to the cell surface.
- Research Organization:
- Department of Anatomy, Duke University Medical Center, Durham, North Carolina
- OSTI ID:
- 6225819
- Journal Information:
- Cell; (United States), Vol. 31:3
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
PHOSPHORUS 32
TRACER TECHNIQUES
PHOSPHOTRANSFERASES
ENZYME ACTIVITY
RETINA
BIOCHEMISTRY
TRITIUM COMPOUNDS
CHICKENS
EMBRYOS
NERVE CELLS
OLIGOSACCHARIDES
STRUCTURAL CHEMICAL ANALYSIS
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIRDS
BODY
BODY AREAS
CARBOHYDRATES
CHEMISTRY
DAYS LIVING RADIOISOTOPES
ENZYMES
EYES
FACE
FOWL
HEAD
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LIGHT NUCLEI
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANS
PHOSPHORUS ISOTOPES
PHOSPHORUS-GROUP TRANSFERASES
RADIOISOTOPES
SACCHARIDES
SENSE ORGANS
SOMATIC CELLS
TRANSFERASES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques