Viral small nuclear ribonucleoproteins bind a protein implicated in messenger RNA destabilization.
Herpesvirus saimiri (HVS) is one of several primate viruses that carry genes for small RNAs. The five H. saimiri-encoded U RNAs (HSURs) are the most abundant viral transcripts expressed in transformed marmoset T lymphocytes. They assemble with host proteins common to spliceosomal small nuclear ribonucleoproteins (snRNPs). HSURs 1, 2, and 5 exhibit sequences at their 5' ends identical to the AUUUA motif, which targets a number of protooncogene, cytokine, and lymphokine mRNAs for rapid degradation. We show that a 32-kDa protein previously demonstrated to bind to the 3' untranslated region of several unstable messages can be UV crosslinked specifically to HSUR 1, 2, and 5 transcripts in vitro, as well as to endogenous HSUR snRNPs. Our results suggest an unusual role for these viral snRNPs: HSURs may function to attenuate the rapid degradation of certain cellular mRNAs, thereby facilitating viral transformation of host T lymphocytes.
Myer
V E
VE
Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University, Congress Avenue, New Haven, CT 06536-0182.
Lee
S I
SI
Steitz
J A
JA
D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D006567:Herpesvirus 2, Saimiriine / Q000235:genetics*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism*; D012367:RNA, Viral / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000378:metabolism* / Q000528:radiation effects; D017411:Ribonucleoproteins, Small Nuclear; D014466:Ultraviolet Rays
D009687:Nuclear Proteins; D012333:RNA, Messenger; D012367:RNA, Viral; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear