The binding of apobec-1 to mammalian apo B RNA is stabilized by the presence of complementation factors which are required for post-transcriptional editing.
C to U RNA editing in mammalian intestinal apolipoprotein B mRNA creates an in-frame translational stop and the synthesis of a truncated protein called apo B48. This site specific cytidine deamination is mediated by an enzyme complex of which the catalytic component (apobec-1) is a 27 kDa zinc-binding protein. apobec-1, expressed in bacteria, will bind to mammalian apo B RNA as well as a number of other AU-rich RNA templates. Apo B RNA-binding activity can be competed by the addition of tRNA, an effect which can be overcome by the addition of complementation factors such as chick enterocyte S-100 extracts. Thus, apobec-1 may be a non-specific RNA binding protein which requires the presence of complementation factors to stabilize and enhance its binding in the setting of the holo-enzyme.
Anant
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Department of Medicine, University of Chicago, IL 60637, USA.
MacGinnitie
A J
AJ
Davidson
N O
NO
D000071479:APOBEC-1 Deaminase; D000818:Animals; D001055:Apolipoproteins B / Q000235:genetics*; D002645:Chickens; D003432:Cross-Linking Reagents; D003564:Cytidine Deaminase / Q000378:metabolism*; D004795:Enzyme Stability; D005982:Glutathione Transferase / Q000378:metabolism; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000378:metabolism; D012313:RNA / Q000235:genetics* / Q000378:metabolism*; D017393:RNA Editing; D012323:RNA Processing, Post-Transcriptional; D012343:RNA, Transfer / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014466:Ultraviolet Rays; D000098830:AICDA (Activation-Induced Cytidine Deaminase)
D001055:Apolipoproteins B; D003432:Cross-Linking Reagents; D011993:Recombinant Fusion Proteins; D012313:RNA; D012343:RNA, Transfer; D005982:Glutathione Transferase; D000098830:AICDA (Activation-Induced Cytidine Deaminase); D000071479:APOBEC-1 Deaminase; D003564:Cytidine Deaminase