Published:
National Academy of Sciences of the United States of America, 1994
Published in:
Proceedings of the National Academy of Sciences of the United States of America, 91 (1994) 15, Seite 6924-6928
Language:
English
ISSN:
0027-8424
Origination:
Footnote:
Description:
Recent in vitro results suggest that the heterogeneous nuclear ribonucleoparticle (hnRNP) A1 protein modulates alternative splicing by favoring distal 5' splice site (5' SS) selection and exon skipping. We used a mouse erythroleukemia (MEL) cell line (CB3C7) deficient in the expression of hnRNP A1 to test whether variations in hnRNP A1 and A1Bprotein levels affected alternative splicing in vivo. In contrast to A1-expressing MEL cell lines, CB3C7 cells preferentially selected the proximal 13S and 12S 5' SS on the adenovirus E1A pre-mRNA. Transiently expressing the A1 or A1BcDNA in CB3C7 cells shifted 5' SS selection toward the more distal 9S donor site. A1 protein synthesis was required for this effect since the expression of a mutated A1 cDNA did not affect 5' SS selection. These results demonstrate that in vivo variations in hnRNP A1 protein levels can influence 5' SS selection.