Recognition of polyadenosine RNA by zinc finger proteins.
Messenger RNA transcripts are coated from cap to tail with a dynamic combination of RNA binding proteins that process, package, and ultimately regulate the fate of mature transcripts. One class of RNA binding proteins essential for multiple aspects of mRNA metabolism consists of the poly(A) binding proteins. Previous studies have concentrated on the canonical RNA recognition motif-containing poly(A) binding proteins as the sole family of poly(A)-specific RNA binding proteins. In this study, we present evidence for a previously uncharacterized poly(A) recognition motif consisting of tandem CCCH zinc fingers. We have probed the nucleic acid binding properties of a yeast protein, Nab2, that contains this zinc finger motif. Results of this study reveal that the seven tandem CCCH zinc fingers of Nab2 specifically bind to polyadenosine RNA with high affinity. Furthermore, we demonstrate that a human protein, ZC3H14, which contains CCCH zinc fingers homologous to those found in Nab2, also specifically binds polyadenosine RNA. Thus, we propose that these proteins are members of an evolutionarily conserved family of poly(A) RNA binding proteins that recognize poly(A) RNA through a fundamentally different mechanism than previously characterized RNA recognition motif-containing poly(A) binding proteins.
Kelly
Seth M
SM
Department of Biochemistry and Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA.
Pabit
Suzette A
SA
Kitchen
Chad M
CM
Guo
Peng
P
Marfatia
Kavita A
KA
Murphy
T J
TJ
Corbett
Anita H
AH
Berland
Keith M
KM
D000241:Adenosine / Q000378:metabolism*; D000595:Amino Acid Sequence; D017124:Conserved Sequence; D006801:Humans; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D029543:Nucleocytoplasmic Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D039102:Poly(A)-Binding Proteins; D011108:Polymers / Q000378:metabolism*; D011485:Protein Binding; D012313:RNA / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016335:Zinc Fingers
C080773:NAB2 protein, S cerevisiae; D009687:Nuclear Proteins; D029543:Nucleocytoplasmic Transport Proteins; D039102:Poly(A)-Binding Proteins; D011108:Polymers; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; C522547:ZC3H14 protein, human; C069424:polyadenosine; D012313:RNA; D000241:Adenosine