Alternative splicing of the fibronectin EIIIB exon depends on specific TGCATG repeats.
The fibronectin EIIIB exon is alternatively spliced in a cell-type-specific manner, and TGCATG repeats in the intron downstream of EIIIB have been implicated in this regulation. Analysis of the intron sequence from several vertebrates shows that the pattern of repeats in the 3' half of the intron is evolutionarily conserved. Point mutations in certain highly conserved repeats greatly reduce EIIIB inclusion, suggesting that a multicomponent complex may recognize the repeats. Expression of the SR protein SRp40, SRp20, or ASF/SF2 stimulates EIIIB inclusion. Studies of the interplay between mutations in the repeats and SRp40-stimulated inclusion suggest that the repeats are recognized in many, if not all, cell types, and that EIIIB inclusion may be regulated by quantitative changes in multiple factors.
Lim
L P
LP
Center for Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Sharp
P A
PA
D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D019556:COS Cells; D002460:Cell Line; D002645:Chickens; D017124:Conserved Sequence; D019143:Evolution, Molecular; D005091:Exons; D005353:Fibronectins / Q000235:genetics*; D016153:Genes, Suppressor; D006801:Humans; D007438:Introns; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D051381:Rats; D014162:Transfection; D014982:Xenopus laevis
D005353:Fibronectins