Phosphorylation of spliceosomal protein SAP 155 coupled with splicing catalysis.
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ABSTRACT:
SUBMITTER: Wang C
PROVIDER: S-EPMC316838 | biostudies-literature | 1998 May
REPOSITORIES: biostudies-literature
Publications
Phosphorylation of spliceosomal protein SAP 155 coupled with splicing catalysis.
Wang C C Chua K K Seghezzi W W Lees E E Gozani O O Reed R R
Genes & development 19980501 10
The U2 snRNP component SAP 155 contacts pre-mRNA on both sides of the branch site early in spliceosome assembly and is therefore positioned near or at the spliceosome catalytic center. We have isolated a cDNA encoding human SAP 155 and identified its highly related Saccharomyces cerevisiae homolog (50% identity). The carboxy-terminal two-thirds of SAP 155 shows the highest conservation and is remarkably similar to the regulatory subunit A of the phosphatase PP2A. Significantly, SAP 155 is phosph ...[more]
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