Previous Article | Next Article ![]()
Mol. Cell. Biol., 11 1995, 6273-6282, Vol 15, No. 11
X Peng and SM Mount
SR proteins are essential for pre-mRNA splicing in vitro, act early in the
splicing pathway, and can influence alternative splice site choice. Here we
describe the isolation of both dominant and loss-of-function alleles of
B52, the gene for a Drosophila SR protein. The allele B52ED was identified
as a dominant second-site enhancer of white-apricot (wa), a retrotransposon
insertion in the second intron of the eye pigmentation gene white with a
complex RNA-processing defect. B52ED also exaggerates the mutant phenotype
of a distinct white allele carrying a 5' splice site mutation (wDR18), and
alters the pattern of sex-specific splicing at doublesex under sensitized
conditions, so that the male-specific splice is favored. In addition to
being a dominant enhancer of these RNA-processing defects, B52ED is a
recessive lethal allele that fails to complement other lethal alleles of
B52. Comparison of B52ED with the B52+ allele from which it was derived
revealed a single change in a conserved amino acid in the beta 4 strand of
the first RNA-binding domain of B52, which suggests that altered RNA
binding is responsible for the dominant phenotype. Reversion of the B52ED
dominant allele with X rays led to the isolation of a B52 null allele.
Together, these results indicate a critical role for the SR protein B52 in
pre-mRNA splicing in vivo.
Copyright © 1995, American Society for Microbiology
Genetic enhancement of RNA-processing defects by a dominant mutation in B52, the Drosophila gene for an SR protein splicing factor
Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»