Regulation of HLA class II expression in mutants of blymphoblastoid cell lines

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6601251

Koppleman, B D

In an effort to identify factors involved in the regulation of the expression of human major histocompatibility complex class II antigens, a series of mutants were derived that failed to express certain of these molecules on their plasma membranes. This was accomplished by exposing the cells to {gamma}-irradiation and selecting for the loss of expression of class II antigens using antibody and complement. One such mutant designated HMy2.DRN no longer expressed HLA-DR molecules on its cell surface. Cell surface expression was found to be restored by transfecting a wildtype DRA but not a DRB cDNA suggesting a structural mutation in the DRA mRNA or protein was responsible for the lack of cell surface expression. Nucleotide sequence analysis of the DRA mRNA from HMy2.DRN revealed a 75 nucleotide deletion corresponding to the start of the {alpha}2 domain and involving one of two cysteines that are involved in the formation of an intrachain disulfide bond. At the biochemical level, only minute quantities of HLA-DR could be precipitated from this cell line following a 4 hour continuous label with {sup 35}S-methionine. HLA-DR{beta} and the class II associated invariant chain could be seen coprecipitating with the mutant DR suggesting a process of normal assembly. However by carrying out the labeling at 16{degree}C instead of 37{degree}C, equivalent amounts of HLA-DR could be precipitated from parent and mutant alike.

• Research Organization: Duke Univ., Durham, NC (USA)
• OSTI ID: 6601251
• Country of Publication: United States
• Language: English

Related Subjects

550201 -- Biochemistry-- Tracer Techniques
560120* -- Radiation Effects on Biochemicals
Cells
& Tissue Culture
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINO ACID SEQUENCE
AMINO ACIDS
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CELL MEMBRANES
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
DRUGS
EVEN-ODD NUCLEI
GENE REGULATION
ISOTOPE APPLICATIONS
ISOTOPES
LEUKOCYTES
LIGHT NUCLEI
LIPOTROPIC FACTORS
LYMPHOCYTES
MAMMALS
MAN
MATERIALS
MEMBRANES
MESSENGER-RNA
METHIONINE
MOLECULAR STRUCTURE
MUTANTS
NUCLEI
NUCLEIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PRIMATES
RADIATION INDUCED MUTANTS
RADIOISOTOPES
RNA
SOMATIC CELLS
SULFUR 35
SULFUR ISOTOPES
TRACER TECHNIQUES
VERTEBRATES