RNA interference (RNAi)-dependent and RNAi-independent association of the Chp1 chromodomain protein with distinct heterochromatic loci in fission yeast.
The establishment of centromeric heterochromatin in the fission yeast Schizosaccharomyces pombe is dependent on the RNA interference (RNAi) pathway. Dicer cleaves centromeric transcripts to produce short interfering RNAs (siRNAs) that actively recruit components of heterochromatin to centromeres. Both centromeric siRNAs and the heterochromatin component Chp1 are components of the RITS (RNA-induced initiation of transcriptional gene silencing) complex, and the association of RITS with centromeres is linked to Dicer activity. In turn, centromeric binding of RITS promotes Clr4-mediated methylation of histone H3 lysine 9 (K9), recruitment of Swi6, and formation of heterochromatin. Similar to centromeres, the mating type locus (Mat) is coated in K9-methylated histone H3 and is bound by Swi6. Here we report that Chp1 associates with the mating type locus and telomeres and that Chp1 localization to heterochromatin depends on its chromodomain and the C-terminal domain of the protein. Another protein component of the RITS complex, Tas3, also binds to Mat and telomeres. Tas3 interacts with Chp1 through the C-terminal domain of Chp1, and this interaction is necessary for Tas3 stability. Interestingly, in cells lacking the Argonaute (Ago1) protein component of the RITS complex, or lacking Dicer (and hence siRNAs), Chp1 and Tas3 can still bind to noncentromeric loci, although their association with centromeres is lost. Thus, Chp1 and Tas3 exist as an Ago1-independent subcomplex that associates with noncentromeric heterochromatin independently of the RNAi pathway.
Petrie
Victoria J
VJ
Department of Biochemistry, St. Jude Children's Research Hospital, 332 N. Lauderdale, Memphis, TN 38105, USA.
Wuitschick
Jeffrey D
JD
Givens
Cheryl D
CD
Kosinski
Aaron M
AM
Partridge
Janet F
JF
D060565:Argonaute Proteins; D002352:Carrier Proteins / Q000032:analysis / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000737:chemistry; D002503:Centromere / Q000737:chemistry / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D006570:Heterochromatin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D016601:RNA-Binding Proteins; D034743:RNA-Induced Silencing Complex / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
C481643:Ago1 protein, S pombe; D060565:Argonaute Proteins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; C115018:Chp1 protein, S pombe; D006570:Heterochromatin; D016601:RNA-Binding Proteins; D034743:RNA-Induced Silencing Complex; D029702:Schizosaccharomyces pombe Proteins; C499720:Tas3 protein, S pombe
Curr Biol. 2002 Oct 1;12(19):1652-60
12361567
EMBO J. 2004 Oct 1;23(19):3825-35
15372076
Proc Natl Acad Sci U S A. 2002 Dec 24;99(26):16648-53
12482946
Proc Natl Acad Sci U S A. 2003 Jan 7;100(1):193-8
12509501
Chromosome Res. 2003;11(2):137-46
12733640
EMBO J. 2003 Jun 16;22(12):3164-74
12805230
Genes Dev. 2003 Sep 15;17(18):2271-82
12952894
Curr Biol. 2003 Oct 14;13(20):1748-57
14561399
Curr Biol. 2003 Dec 2;13(23):R895-8
14654010
Science. 2004 Jan 30;303(5658):672-6
14704433
Science. 2004 Jun 25;304(5679):1971-6
15218150
Genes Dev. 2004 Oct 1;18(19):2359-67
15371329
J Biol Chem. 2004 Oct 8;279(41):42850-9
15292231
Nat Genet. 2004 Nov;36(11):1174-80
15475954
Methods Enzymol. 1987;154:164-75
3323810
J Cell Sci. 1988 Mar;89 ( Pt 3):343-57
3198697
J Cell Sci. 1989 Jul;93 ( Pt 3):491-500
2606940
J Biol Chem. 1990 Oct 5;265(28):17174-9
2211619
Methods Enzymol. 1991;194:795-823
2005825
Gene. 1993 Jan 15;123(1):131-6
8422997
J Cell Biol. 1993 Jun;121(5):961-76
8388878
Genetics. 1994 Jan;136(1):53-64
8138176
Science. 1994 Apr 8;264(5156):270-3
8146661
Genes Dev. 1995 Jan 15;9(2):218-33
7851795
Science. 1995 Sep 8;269(5229):1429-31
7660126
Semin Cell Biol. 1995 Apr;6(2):55-64
7548843
J Cell Sci. 1996 Nov;109 ( Pt 11):2637-48
8937982
Genetics. 1997 Aug;146(4):1221-38
9258669
Cell. 1997 Dec 26;91(7):1021-32
9428524
Yeast. 1998 Jul;14(10):943-51
9717240
Nucleic Acids Res. 1998 Sep 15;26(18):4222-9
9722643
Genes Dev. 2000 Apr 1;14(7):783-91
10766735
Genetics. 2000 Jun;155(2):551-68
10835380
Science. 2000 Jun 23;288(5474):2215-9
10864871
Genetics. 2000 Nov;156(3):983-94
11063679
Nature. 2001 Mar 1;410(6824):120-4
11242054
Yeast. 2001 May;18(7):657-62
11329175
Mol Biol Cell. 2001 Sep;12(9):2767-75
11553715
Science. 2002 Sep 13;297(5588):1833-7
12193640
Science. 2002 Sep 13;297(5588):1831
12193644
Science. 2002 Sep 27;297(5590):2232-7
12215653
Genetics. 1999 Mar;151(3):945-63
10049914
Cell. 2002 Oct 18;111(2):159-62
12408860