Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1998-4-23
pubmed:abstractText
Class II MHC molecules are heterodimeric transmembrane glycoproteins that function in the presentation of Ag to CD4+ T cells. Deletion of the cytoplasmic domains of the murine class II A alpha- and A beta-chains has previously been shown to diminish Ag presentation and abrogate rejection of class II-transfected tumor cells. To examine the contributions of individual amino acid residues of the A beta cytoplasmic domain to Ag presentation and tumor rejection, we have produced a series of cell lines expressing A beta class II molecules with site-directed mutations. An A beta(k) cDNA was constructed with mutations in the five conserved amino acid residues, Q224, K225, L235, L236, and Q237 (delta5). In addition, cDNA were produced in which alanine was individually substituted for A beta(k) cytoplasmic domain residues 224 through 237 or doubly substituted at residues G226 and P227 or L235 and L236. These mutant cDNAs were individually cotransfected with wild-type A alpha cDNA into the class II-negative M12.C3 B lymphoma and Sal sarcoma cell lines. As was previously reported for transfectants lacking the entire A beta(k) cytoplasmic domain, the delta5 M12.C3 transfectant could not effectively present Ag to an autoreactive Ak-restricted T cell hybrid, and the delta5 Sal transfectant was not rejected when inoculated into syngeneic hosts. A finer analysis revealed that alteration of the individual residue Q224 or the two residues G226 and P227 abrogated Ag presentation in vitro, while mutation of G226 diminished tumor rejection in vivo. Thus, the function of the A beta cytoplasmic domain in Ag presentation both in vitro and in vivo can be disturbed by mutation of single amino acid residues.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
159
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5914-20
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:9550388-Amino Acid Sequence, pubmed-meshheading:9550388-Amino Acid Substitution, pubmed-meshheading:9550388-Animals, pubmed-meshheading:9550388-Antigen Presentation, pubmed-meshheading:9550388-Cytoplasm, pubmed-meshheading:9550388-Female, pubmed-meshheading:9550388-Graft Rejection, pubmed-meshheading:9550388-Histocompatibility Antigens Class II, pubmed-meshheading:9550388-Humans, pubmed-meshheading:9550388-Lymphoma, B-Cell, pubmed-meshheading:9550388-Male, pubmed-meshheading:9550388-Mice, pubmed-meshheading:9550388-Mice, Inbred A, pubmed-meshheading:9550388-Mice, Inbred BALB C, pubmed-meshheading:9550388-Molecular Sequence Data, pubmed-meshheading:9550388-Mutagenesis, Site-Directed, pubmed-meshheading:9550388-Neoplasm Transplantation, pubmed-meshheading:9550388-Protein Structure, Tertiary, pubmed-meshheading:9550388-Rats, pubmed-meshheading:9550388-Sarcoma, Experimental, pubmed-meshheading:9550388-Sequence Homology, Amino Acid, pubmed-meshheading:9550388-Swine, pubmed-meshheading:9550388-Tumor Cells, Cultured
pubmed:year
1997
pubmed:articleTitle
Single amino acid mutations in the murine MHC class II A beta cytoplasmic domain abrogate antigen presentation.
pubmed:affiliation
Department of Cancer Biology, Harvard School of Public Health, Boston, MA 02115, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.