This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Terns, M P Articles by Jacob, S T Search for Related Content PubMed PubMed Citation Articles by Terns, M P Articles by Jacob, S T

Role of poly(A) polymerase in the cleavage and polyadenylation of mRNA precursor.

Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey 17033.

ABSTRACT

To determine the role of poly(A) polymerase in 3'-end processing of mRNA, the effect of purified poly(A) polymerase antibodies on endonucleolytic cleavage and polyadenylation was studied in HeLa nuclear extracts, using adenovirus L3 pre-mRNA as the substrate. Both Mg2+- and Mn2+-dependent reactions catalyzing addition of 200 to 250 and 400 to 800 adenylic acid residues, respectively, were inhibited by the antibodies, which suggested that the two reactions were catalyzed by the same enzyme. Anti-poly(A) polymerase antibodies also inhibited the cleavage reaction when the reaction was coupled or chemically uncoupled with polyadenylation. These antibodies also prevented formation of specific complexes between the RNA substrate and components of nuclear extracts during cleavage or polyadenylation, with the concurrent appearance of another, antibody-specific complex. These studies demonstrate that (i) previously characterized poly(A) polymerase is the enzyme responsible for addition of the poly(A) tract at the correct cleavage site and probably for the elongation of poly(A) chains and (ii) the coupling of these two 3'-end processing reactions appears to result from the potential requirement of poly(A) polymerase for the cleavage reaction. The results suggest that the specific endonuclease is associated with poly(A) polymerase in a functional complex.

This article has been cited by other articles:

• Takagaki, Y, Manley, J L, MacDonald, C C, Wilusz, J, Shenk, T (1990). A multisubunit factor, CstF, is required for polyadenylation of mammalian pre-mRNAs.. Genes Dev. 4: 2112-2120 [Abstract]  
• Russnak, R, Ganem, D (1990). Sequences 5' to the polyadenylation signal mediate differential poly(A) site use in hepatitis B viruses.. Genes Dev. 4: 764-776 [Abstract]