Identification of Apurinic/apyrimidinic endonuclease 1 (APE1) as the endoribonuclease that cleaves c-myc mRNA

Endonucleolytic cleavage of the coding region determinant (CRD) of c-myc mRNA appears to play a critical role in regulating c-myc mRNA turnover. Using 32P-labeled c-myc CRD RNA as substrate, we have purified and identified two endoribonucleases from rat liver polysomes that are capable of cleaving t...

Full description

Saved in:
Bibliographic Details
Published in:Nucleic acids research 2009-07, Vol.37 (12), p.3946-3958
Main Authors: Barnes, Tavish, Kim, Wan-Cheol, Mantha, Anil K, Kim, Sang-Eun, Izumi, Tadahide, Mitra, Sankar, Lee, Chow H
Format: Article
Language:English
Subjects:
Animals
Antibodies, Monoclonal
DNA-(Apurinic or Apyrimidinic Site) Lyase - chemistry
DNA-(Apurinic or Apyrimidinic Site) Lyase - immunology
DNA-(Apurinic or Apyrimidinic Site) Lyase - metabolism
Endoribonucleases - chemistry
Endoribonucleases - isolation & purification
Endoribonucleases - metabolism
HeLa Cells
Humans
Liver - enzymology
Nucleic Acids Enzymes
Proto-Oncogene Proteins c-myc - genetics
Proto-Oncogene Proteins c-myc - metabolism
Rats
Recombinant Proteins - metabolism
Ribonuclease, Pancreatic - classification
RNA Interference
RNA, Messenger - metabolism
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Endonucleolytic cleavage of the coding region determinant (CRD) of c-myc mRNA appears to play a critical role in regulating c-myc mRNA turnover. Using 32P-labeled c-myc CRD RNA as substrate, we have purified and identified two endoribonucleases from rat liver polysomes that are capable of cleaving the transcript in vitro. A 17-kDa enzyme was identified as RNase1. Apurinic/apyrimidinic (AP) DNA endonuclease 1 (APE1) was identified as the 35-kDa endoribonuclease that preferentially cleaves in between UA and CA dinucleotides of c-myc CRD RNA. APE1 was further confirmed to be the 35-kDa endoribonuclease because: (i) the endoribonuclease activity of the purified 35-kDa native enzyme was specifically immuno-depleted with APE1 monoclonal antibody, and (ii) recombinant human APE1 generated identical RNA cleavage patterns as the native liver enzyme. Studies using E96A and H309N mutants of APE1 suggest that the endoribonuclease activity for c-myc CRD RNA shares the same active center with the AP-DNA endonuclease activity. Transient knockdown of APE1 in HeLa cells led to increased steady-state level of c-myc mRNA and its half-life. We conclude that the ability to cleave RNA dinucleotides is a previously unidentified function of APE1 and it can regulate c-myc mRNA level possibly via its endoribonuclease activity.
ISSN:0305-1048
1362-4962
DOI:10.1093/nar/gkp275