Refractoriness of hepatitis C virus internal ribosome entry site to processing by Dicer in vivo.
BACKGROUND
Hepatitis C virus (HCV) is a positive-strand RNA virus harboring a highly structured internal ribosome entry site (IRES) in the 5' nontranslated region of its genome. Important for initiating translation of viral RNAs into proteins, the HCV IRES is composed of RNA structures reminiscent of microRNA precursors that may be targeted by the host RNA silencing machinery.


RESULTS
We report that HCV IRES can be recognized and processed into small RNAs by the human ribonuclease Dicer in vitro. Furthermore, we identify domains II, III and VI of HCV IRES as potential substrates for Dicer in vitro. However, maintenance of the functional integrity of the HCV IRES in response to Dicer overexpression suggests that the structure of the HCV IRES abrogates its processing by Dicer in vivo.


CONCLUSIONS
Our results suggest that the HCV IRES may have evolved to adopt a structure or a cellular context that is refractory to Dicer processing, which may contribute to viral escape of the host RNA silencing machinery.
Ouellet
Dominique L
DL
Centre de Recherche en Rhumatologie et Immunologie, CHUL Research Center/CHUQ, 2705 Blvd Laurier, Quebec, QC, G1V 4G2, Canada. dominique.ouellet@crchul.ulaval.ca
Plante
Isabelle
I
Boissonneault
Vincent
V
Ayari
Cherifa
C
Provost
Patrick
P
D001483:Base Sequence; D002460:Cell Line; D016174:Hepacivirus / Q000201:enzymology* / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D011485:Protein Binding / Q000235:genetics; D017434:Protein Structure, Tertiary / Q000235:genetics; D034622:RNA Interference / Q000502:physiology; D012323:RNA Processing, Post-Transcriptional / Q000235:genetics*; D012335:RNA, Ribosomal / Q000235:genetics / Q000378:metabolism*; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism*; D043244:Ribonuclease III / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012270:Ribosomes / Q000201:enzymology*; D013379:Substrate Specificity / Q000235:genetics; D053586:Virus Internalization
D012335:RNA, Ribosomal; D012367:RNA, Viral; D043244:Ribonuclease III
Nucleosides Nucleotides Nucleic Acids. 2006;25(7):801-5
16898418
Methods. 2002 Feb;26(2):182-90
12054895
J Viral Hepat. 1999 Mar;6(2):79-87
10607219
Science. 2002 May 17;296(5571):1319-21
12016316
EMBO J. 2002 Nov 1;21(21):5875-85
12411505
J Med Virol. 2002 Feb;66(2):187-99
11782927
J Virol. 2006 Jun;80(12):5747-56
16731914
J Biol Chem. 2002 Jan 4;277(1):593-601
11641406
Exp Mol Pathol. 2004 Jun;76(3):242-52
15126107
J Gen Virol. 2008 Nov;89(Pt 11):2761-2766
18931073
Immunity. 2005 May;22(5):607-19
15894278
J Virol. 1993 Jun;67(6):3338-44
8388503
Retrovirology. 2006 Dec 20;3:95
17181864
J Proteome Res. 2004 Sep-Oct;3(5):949-57
15473682
Gastroenterology. 2006 Mar;130(3):883-92
16530526
J Hepatol. 2005 Aug;43(2):225-34
15964661
Science. 2004 Apr 30;304(5671):734-6
15118162
J Virol. 1998 Nov;72(11):8782-8
9765422
J Gen Virol. 2001 Apr;82(Pt 4):723-733
11257176
J Biomed Biotechnol. 2006;2006(4):64347
17057366
J Virol. 2007 Jan;81(2):669-76
17079316
Proc Natl Acad Sci U S A. 2004 Feb 3;101(5):1350-5
14745017
Genes Dev. 2005 Dec 15;19(24):2979-90
16357216
Nat Methods. 2005 Apr;2(4):269-76
15782219
Proc Natl Acad Sci U S A. 2003 Mar 4;100(5):2783-8
12594341
Virology. 2006 Feb 20;345(2):434-45
16297950
J Biol Chem. 2003 Apr 4;278(14):12231-40
12540850
Virus Res. 2008 May;133(2):250-8
18325616
Retrovirology. 2004 Dec 15;1:44
15601474
J Biomed Sci. 2006 Nov;13(6):861-74
16927014
Science. 1999 Jul 2;285(5424):110-3
10390360
Science. 2005 Sep 2;309(5740):1577-81
16141076
J Virol. 1993 Mar;67(3):1385-95
7679746
Nature. 2007 Oct 18;449(7164):919-22
17943132
Virus Res. 2001 Jan;73(1):67-79
11163645
EMBO J. 2002 Nov 1;21(21):5864-74
12411504
Curr Top Microbiol Immunol. 2000;242:85-116
10592657
Proc Natl Acad Sci U S A. 1991 Mar 15;88(6):2451-5
1848704
J Hepatol. 2009 Mar;50(3):453-60
19144437
Nature. 2004 May 20;429(6989):318-322
15152257
Genes Dev. 2002 Jul 1;16(13):1616-26
12101121
J Biol Chem. 2009 Jan 23;284(4):1971-81
18986979
Mol Biol Cell. 2006 Nov;17(11):4632-44
16928960
J Virol. 1992 Mar;66(3):1476-83
1310759
Proc Natl Acad Sci U S A. 2005 Apr 12;102(15):5570-5
15800047
Nature. 2003 Sep 25;425(6956):415-9
14508493
Nature. 2005 Aug 4;436(7051):740-4
15973356
J Virol. 1995 Oct;69(10):6367-75
7666538
Nat Struct Biol. 2000 Dec;7(12):1105-10
11101890
Science. 1999 Oct 29;286(5441):950-2
10542148
J Virol. 2004 Dec;78(23):12868-76
15542639
J Virol. 2005 Jan;79(1):234-44
15596819
Mol Cell Biol. 2001 Dec;21(24):8357-64
11713272
EMBO Rep. 2003 Jun;4(6):602-8
12740604
J Gen Virol. 2003 Mar;84(Pt 3):535-543
12604803
Cell. 2004 Jul 9;118(1):57-68
15242644
Cell. 2004 Jan 23;116(2):281-97
14744438
J Virol. 1999 Feb;73(2):1165-74
9882318
Virus Res. 2006 Nov;121(2):107-15
16889864
J Biol Chem. 2005 May 6;280(18):17737-48
15760888
Curr Top Microbiol Immunol. 2000;242:55-84
10592656
J Virol. 2000 Mar;74(5):2293-304
10666260
Proc Natl Acad Sci U S A. 2003 Jan 7;100(1):235-40
12518066
J Biomed Biotechnol. 2006;2006(4):69616
17057368
Gastroenterology. 2005 Feb;128(2):449-62
15685555
Nucleic Acids Res. 2008 Apr;36(7):2353-65
18299284
Hepatology. 2002 Nov;36(5 Suppl 1):S245-52
12407600