A second-step splicing activity is conserved from yeast to human.
نویسندگان
چکیده
We describe a defective HeLa nuclear extract which is particularly deficient in step 2 of splicing reaction. With this extract we have studied the conservation of a second-step activity from yeast to human cells. We detected a S. cerevisiae second-step splicing activity that allows restoration of step 2 of the defective HeLa nuclear extract, which indicates that yeast purified fraction has a second-step activity that is conserved from yeast to human cells. The activity is a yeast UsnRNP protein(s) since it is purified with anti-trimethylguanosine by immunoaffinity columns.
منابع مشابه
A human protein required for the second step of pre-mRNA splicing is functionally related to a yeast splicing factor.
We have identified a human splicing factor required for the second step of pre-mRNA splicing. This new protein, hPrp18, is 30% identical to the yeast splicing factor Prp18. In HeLa cell extracts immunodepleted of hPrp18, the second step of pre-mRNA splicing is abolished. Splicing activity is restored by the addition of recombinant hPrp18, demonstrating that hPrp18 is required for the second ste...
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ورودعنوان ژورنال:
- Biochemical and biophysical research communications
دوره 247 2 شماره
صفحات -
تاریخ انتشار 1998