| | |
Summary: Reversible inhibition of the second step of splicing
suggests a possible role of zinc in the second step
of splicing
Noam Shomron, Hadar Malca, Ida Vig and Gil Ast*
Department of Human Genetics and Molecular Medicine, Sackler School of Medicine, Tel Aviv University,
Ramat Aviv 69978, Tel Aviv, Israel
Received July 10, 2002; Revised and Accepted August 15, 2002
ABSTRACT
A multicomponent complex of proteins and RNA is
assembled on the newly synthesized pre-mRNA to
form the spliceosome. This complex catalyzes a
two-step transesteri®cation reaction required to
remove the introns and ligate the exons. To date,
only six proteins have been found necessary for the
second step of splicing in yeast, and their human
homologs have been identi®ed. We demonstrate
that the addition of the selective chelator of zinc,
1,10-phenanthroline, to an in vitro mRNA splicing
reaction causes a dose-dependent inhibition of the
second step of splicing. This inhibition is accom-
|
