|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
doi: 10.1242/10.1242/dev.00405
1 Department of Biochemistry, University of Iowa, Iowa City, IA 52242, USA
2 Department of Cell and Structural Biology, University of Illinois,
Urbana-Champaign, Urbana, IL 61801, USA
* Author for correspondence (e-mail: lori-wallrath{at}uiowa.edu)
Accepted 13 January 2003
Heterochromatin protein 1 (HP1) is a conserved non-histone chromosomal protein enriched in heterochromatin. On Drosophila polytene chromosomes, HP1 localizes to centric and telomeric regions, along the fourth chromosome, and to specific sites within euchromatin. HP1 associates with centric regions through an interaction with methylated lysine nine of histone H3, a modification generated by the histone methyltransferase SU(VAR)3-9. This association correlates with a closed chromatin configuration and silencing of euchromatic genes positioned near heterochromatin. To determine whether HP1 is sufficient to nucleate the formation of silent chromatin at non-centric locations, HP1 was tethered to sites within euchromatic regions of Drosophila chromosomes. At 25 out of 26 sites tested, tethered HP1 caused silencing of a nearby reporter gene. The site that did not support silencing was upstream of an active gene, suggesting that the local chromatin environment did not support the formation of silent chromatin. Silencing correlated with the formation of ectopic fibers between the site of tethered HP1 and other chromosomal sites, some containing HP1. The ability of HP1 to bring distant chromosomal sites into proximity with each other suggests a mechanism for chromatin packaging. Silencing was not dependent on SU(VAR)3-9 dosage, suggesting a bypass of the requirement for histone methylation.
Key words: Gene silencing, Drosophila, Heterchromatin protein 1 (HP1)
This article has been cited by other articles:
![]() |
H. Deng, X. Bao, W. Cai, M. J. Blacketer, A. S. Belmont, J. Girton, J. Johansen, and K. M. Johansen Ectopic histone H3S10 phosphorylation causes chromatin structure remodeling in Drosophila Development, February 15, 2008; 135(4): 699 - 705. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Deng, X. Bao, W. Zhang, J. Girton, J. Johansen, and K. M. Johansen Reduced Levels of Su(var)3-9 But Not Su(var)2-5 (HP1) Counteract the Effects on Chromatin Structure and Viability in Loss-of-Function Mutants of the JIL-1 Histone H3S10 Kinase Genetics, September 1, 2007; 177(1): 79 - 87. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Eskeland, A. Eberharter, and A. Imhof HP1 Binding to Chromatin Methylated at H3K9 Is Enhanced by Auxiliary Factors Mol. Cell. Biol., January 15, 2007; 27(2): 453 - 465. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. J. Verschure, I. van der Kraan, W. de Leeuw, J. van der Vlag, A. E. Carpenter, A. S. Belmont, and R. van Driel In Vivo HP1 Targeting Causes Large-Scale Chromatin Condensation and Enhanced Histone Lysine Methylation Mol. Cell. Biol., June 1, 2005; 25(11): 4552 - 4564. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. De Lucia, J.-Q. Ni, C. Vaillant, and F.-L. Sun HP1 modulates the transcription of cell-cycle regulators in Drosophila melanogaster Nucleic Acids Res., May 19, 2005; 33(9): 2852 - 2858. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Delattre, A. Spierer, Y. Jaquet, and P. Spierer Increased expression of Drosophila Su(var)3-7 triggers Su(var)3-9-dependent heterochromatin formation J. Cell Sci., December 1, 2004; 117(25): 6239 - 6247. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. D. Carvin and M. P. Kladde Effectors of Lysine 4 Methylation of Histone H3 in Saccharomyces cerevisiae Are Negative Regulators of PHO5 and GAL1-10 J. Biol. Chem., August 6, 2004; 279(32): 33057 - 33062. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. R. Danzer and L. L. Wallrath Mechanisms of HP1-mediated gene silencing in Drosophila Development, August 1, 2004; 131(15): 3571 - 3580. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Cheutin, S. A. Gorski, K. M. May, P. B. Singh, and T. Misteli In Vivo Dynamics of Swi6 in Yeast: Evidence for a Stochastic Model of Heterochromatin Mol. Cell. Biol., April 15, 2004; 24(8): 3157 - 3167. [Abstract] [Full Text] [PDF] |
||||