The nuclear poly(A) binding protein of mammals, but not of fission yeast, participates in mRNA polyadenylation
| Autor: | Elmar Wahle, Uwe Kühn, Juliane Buschmann |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Polyadenylation Gene Expression Poly(A)-Binding Protein I Poly(A)-Binding Proteins Substrate Specificity 03 medical and health sciences MRNA polyadenylation Species Specificity Report Poly(A)-binding protein Schizosaccharomyces Escherichia coli RNA Precursors Humans RNA Messenger Cloning Molecular Molecular Biology Polymerase Messenger RNA biology Polynucleotide Adenylyltransferase biology.organism_classification Molecular biology Recombinant Proteins Cell biology Isoenzymes 030104 developmental biology HEK293 Cells Gene Expression Regulation Polynucleotide adenylyltransferase biology.protein Schizosaccharomyces pombe Proteins Poly A |
| Zdroj: | RNA (New York, N.Y.). 23(4) |
| ISSN: | 1469-9001 |
| Popis: | The nuclear poly(A) binding protein (PABPN1) has been suggested, on the basis of biochemical evidence, to play a role in mRNA polyadenylation by strongly increasing the processivity of poly(A) polymerase. While experiments in metazoans have tended to support such a role, the results were not unequivocal, and genetic data show that the S. pombe ortholog of PABPN1, Pab2, is not involved in mRNA polyadenylation. The specific model in which PABPN1 increases the rate of poly(A) tail elongation has never been examined in vivo. Here, we have used 4-thiouridine pulse-labeling to examine the lengths of newly synthesized poly(A) tails in human cells. Knockdown of PABPN1 strongly reduced the synthesis of full-length tails of ∼250 nucleotides, as predicted from biochemical data. We have also purified S. pombe Pab2 and the S. pombe poly(A) polymerase, Pla1, and examined their in vitro activities. Whereas PABPN1 strongly increases the activity of its cognate poly(A) polymerase in vitro, Pab2 was unable to stimulate Pla1 to any significant extent. Thus, in vitro and in vivo data are consistent in supporting a role of PABPN1 but not S. pombe Pab2 in the polyadenylation of mRNA precursors. |
| Databáze: | OpenAIRE |
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