title: Functional dissection of the Drosophila melanogaster condensin subunit Cap-G reveals its exclusive association with condensin I.
abstract: The heteropentameric condensin complexes have been shown to participate in mitotic chromosome condensation and to be required for unperturbed chromatid segregation in nuclear divisions. Vertebrates have two condensin complexes, condensin I and condensin II, which contain the same structural maintenance of chromosomes (SMC) subunits SMC2 and SMC4, but differ in their composition of non-SMC subunits. While a clear biochemical and functional distinction between condensin I and condensin II has been established in vertebrates, the situation in Drosophila melanogaster is less defined. Since Drosophila lacks a clear homolog for the condensin II-specific subunit Cap-G2, the condensin I subunit Cap-G has been hypothesized to be part of both complexes. In vivo microscopy revealed that a functional Cap-G-EGFP variant shows a distinct nuclear enrichment during interphase, which is reminiscent of condensin II localization in vertebrates and contrasts with the cytoplasmic enrichment observed for the other EGFP-fused condensin I subunits. However, we show that this nuclear localization is dispensable for Cap-G chromatin association, for its assembly into the condensin I complex and, importantly, for development into a viable and fertile adult animal. Immunoprecipitation analyses and complex formation studies provide evidence that Cap-G does not associate with condensin II-specific subunits, while it can be readily detected in complexes with condensin I-specific proteins in vitro and in vivo. Mass-spectrometric analyses of proteins associated with the condensin II-specific subunit Cap-H2 not only fail to identify Cap-G but also the other known condensin II-specific homolog Cap-D3. As condensin II-specific subunits are also not found associated with SMC2, our results question the existence of a soluble condensin II complex in Drosophila.
authors: Lehrstuhl für Genetik, University of Bayreuth, Bayreuth, Germany.
authors: Sabine
authors: S
authors: Herzog
authors: Sonal
authors: S
authors: Nagarkar Jaiswal
authors: Evelin
authors: E
authors: Urban
authors: Anna
authors: A
authors: Riemer
authors: Sina
authors: S
authors: Fischer
authors: Stefan K
authors: SK
authors: Heidmann
mesh_terms: D000818:Animals; D002842:Chromatids / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D004330:Drosophila / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics
chemical_list: D002843:Chromatin; D029721:Drosophila Proteins
references: Mol Cell Biol. 2005 Oct;25(20):8971-84
references: 16199875
references: Curr Biol. 1997 Jul 1;7(7):468-78
references: 9210377
references: EMBO J. 2007 Feb 21;26(4):1024-34
references: 17268547
references: Leukemia. 2006 Jul;20(7):1261-9
references: 16673016
references: Chromosome Res. 2009;17(2):131-44
references: 19308696
references: Proc Natl Acad Sci U S A. 2007 Jul 24;104(30):12445-50
references: 17640884
references: Curr Biol. 2006 Feb 21;16(4):333-44
references: 16488867
references: PLoS Genet. 2012;8(4):e1002618
references: 22496667
references: Chromosoma. 2005 Feb;113(7):350-61
references: 15592865
references: Genes Dev. 2002 Jun 15;16(12):1498-508
references: 12080088
references: Curr Biol. 2001 Mar 6;11(5):295-307
references: 11267866
references: Genes Dev. 2011 Jul 15;25(14):1464-9
references: 21715560
references: Science. 2006 Dec 15;314(5806):1747-51
references: 17138868
references: J Cell Sci. 2005 Jun 1;118(Pt 11):2529-43
references: 15923665
references: Cell Cycle. 2010 Aug 15;9(16):3243-55
references: 20703077
references: Cell. 1994 Nov 4;79(3):449-58
references: 7954811
references: Mech Dev. 1998 Nov;78(1-2):113-8
references: 9858703
references: Nature. 2002 May 9;417(6885):197-202
references: 12000964
references: Curr Biol. 1998 Feb 12;8(4):239-42
references: 9501988
references: Nat Rev Genet. 2010 Jun;11(6):391-404
references: 20442714
references: J Struct Biol. 2001 May-Jun;134(2-3):117-31
references: 11551174
references: Cell. 2006 Nov 3;127(3):523-37
references: 17081975
references: Curr Biol. 2009 Jan 13;19(1):9-19
references: 19119011
references: J Cell Sci. 2004 Dec 15;117(Pt 26):6435-45
references: 15572404
references: Electrophoresis. 2004 May;25(9):1327-33
references: 15174055
references: Nature. 2011 Jun 01;474(7352):477-83
references: 21633354
references: PLoS Genet. 2008 Oct;4(10):e1000228
references: 18927632
references: Genetics. 2009 Mar;181(3):875-87
references: 19104074
references: J Cell Sci. 1995 Apr;108 ( Pt 4):1407-18
references: 7615662
references: Genetics. 2006 Feb;172(2):991-1008
references: 16272408
references: Cell. 1997 May 16;89(4):511-21
references: 9160743
references: Genes Dev. 2008 Mar 1;22(5):601-14
references: 18316477
references: PLoS Genet. 2012;8(8):e1002873
references: 22956908
references: Genes Dev. 2008 Apr 15;22(8):1011-24
references: 18367646
references: Chromosoma. 2007 Aug;116(4):385-402
references: 17333235
references: Genes Dev. 2012 Aug 1;26(15):1659-78
references: 22855829
references: Cell. 1995 Jul 14;82(1):67-76
references: 7606787
references: Curr Biol. 2003 Dec 2;13(23):2058-64
references: 14653995
references: Mol Cell Biol. 1985 Dec;5(12):3610-6
references: 3915782
references: Mol Cell. 2003 Mar;11(3):571-5
references: 12667442
references: J Cell Sci. 2012 Mar 15;125(Pt 6):1591-604
references: 22344259
references: Mol Biol Cell. 2004 Jul;15(7):3296-308
references: 15146063
references: Cell. 1996 Dec 13;87(6):1103-14
references: 8978614
references: Nature. 2011 Mar 24;471(7339):473-9
references: 21179090
references: Dev Genes Evol. 2000 Dec;210(12):630-7
references: 11151300
references: Development. 1993 Jun;118(2):401-15
references: 8223268
references: Proc Natl Acad Sci U S A. 2007 Feb 27;104(9):3312-7
references: 17360644
references: Mol Cell Biol. 1986 Nov;6(11):3862-72
references: 3099166
references: Genetics. 2004 Oct;168(2):895-906
references: 15514062
references: Science. 2008 Nov 28;322(5906):1384-7
references: 19039137
references: Chromosoma. 2007 Jun;116(3):259-74
references: 17318635
references: Cell. 2003 Oct 3;115(1):109-21
references: 14532007
references: Curr Biol. 2007 Feb 6;17(3):237-43
references: 17222555