Activation-induced changes in alternate splice acceptor site usage.
An AGCAG motif at 3' splice acceptor sites in a diverse set of genes creates alternate in-frame splice acceptor sites that produce alternate protein isoforms differing by a single amino acid. Among a group of over 12,000 EST-verified splice acceptor sites, only 74 genes were identified that contained the AGCAG motif, comprising about 0.7% of the total. In some cases the location of the single amino acid insertion occurs in a region with the potential to affect protein function. Analysis of cDNA from five different human genes of immunologic interest that contain the AGCAG motif, CD3zeta, CD79B, PLCgamma1, CD19, and CD32B (FcgammaRIIB), confirms that each gene encodes the two predicted splice variants. Variations occur in the splice variant ratio in all five of the genes tested during T and B cell activation, suggesting that the ratio is regulated by the cellular activation state. These results suggest that activation-induced variation in mRNA splicing may represent a mechanism for functional modulation of these proteins.
Atkinson
T Prescott
TP
Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35233, USA. patkinso@uab.edu
Dai
Yuling
Y
D017398:Alternative Splicing / Q000235:genetics*; D002478:Cells, Cultured; D002874:Chromosome Mapping; D020224:Expressed Sequence Tags; D006801:Humans; D007963:Leukocytes, Mononuclear; D020033:Protein Isoforms / Q000235:genetics*; D022821:RNA Splice Sites / Q000235:genetics*; D015398:Signal Transduction / Q000235:genetics*; D015533:Transcriptional Activation / Q000235:genetics*
D020033:Protein Isoforms; D022821:RNA Splice Sites