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Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei

ISWI chromatin remodelers are highly conserved in eukaryotes and are important for the assembly and spacing of nucleosomes, thereby controlling transcription initiation and elongation. ISWI is typically associated with different subunits, forming specialized complexes with discrete functions. In the...

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Autores principales: Stanne, Tara, Narayanan, Mani Shankar, Ridewood, Sophie, Ling, Alexandra, Witmer, Kathrin, Kushwaha, Manish, Wiesler, Simone, Wickstead, Bill, Wood, Jennifer, Rudenko, Gloria
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Society for Biochemistry and Molecular Biology 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4646403/
https://www.ncbi.nlm.nih.gov/pubmed/26378228
http://dx.doi.org/10.1074/jbc.M115.679019
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author Stanne, Tara
Narayanan, Mani Shankar
Ridewood, Sophie
Ling, Alexandra
Witmer, Kathrin
Kushwaha, Manish
Wiesler, Simone
Wickstead, Bill
Wood, Jennifer
Rudenko, Gloria
author_facet Stanne, Tara
Narayanan, Mani Shankar
Ridewood, Sophie
Ling, Alexandra
Witmer, Kathrin
Kushwaha, Manish
Wiesler, Simone
Wickstead, Bill
Wood, Jennifer
Rudenko, Gloria
author_sort Stanne, Tara
collection PubMed
description ISWI chromatin remodelers are highly conserved in eukaryotes and are important for the assembly and spacing of nucleosomes, thereby controlling transcription initiation and elongation. ISWI is typically associated with different subunits, forming specialized complexes with discrete functions. In the unicellular parasite Trypanosoma brucei, which causes African sleeping sickness, TbISWI down-regulates RNA polymerase I (Pol I)-transcribed variant surface glycoprotein (VSG) gene expression sites (ESs), which are monoallelically expressed. Here, we use tandem affinity purification to determine the interacting partners of TbISWI. We identify three proteins that do not show significant homology with known ISWI-associated partners. Surprisingly, one of these is nucleoplasmin-like protein (NLP), which we had previously shown to play a role in ES control. In addition, we identify two novel ISWI partners, regulator of chromosome condensation 1-like protein (RCCP) and phenylalanine/tyrosine-rich protein (FYRP), both containing protein motifs typically found on chromatin proteins. Knockdown of RCCP or FYRP in bloodstream form T. brucei results in derepression of silent variant surface glycoprotein ESs, as had previously been shown for TbISWI and NLP. All four proteins are expressed and interact with each other in both major life cycle stages and show similar distributions at Pol I-transcribed loci. They are also found at Pol II strand switch regions as determined with ChIP. ISWI, NLP, RCCP, and FYRP therefore appear to form a single major ISWI complex in T. brucei (TbIC). This reduced complexity of ISWI regulation and the presence of novel ISWI partners highlights the early divergence of trypanosomes in evolution.
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spelling pubmed-46464032015-11-16 Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei Stanne, Tara Narayanan, Mani Shankar Ridewood, Sophie Ling, Alexandra Witmer, Kathrin Kushwaha, Manish Wiesler, Simone Wickstead, Bill Wood, Jennifer Rudenko, Gloria J Biol Chem Microbiology ISWI chromatin remodelers are highly conserved in eukaryotes and are important for the assembly and spacing of nucleosomes, thereby controlling transcription initiation and elongation. ISWI is typically associated with different subunits, forming specialized complexes with discrete functions. In the unicellular parasite Trypanosoma brucei, which causes African sleeping sickness, TbISWI down-regulates RNA polymerase I (Pol I)-transcribed variant surface glycoprotein (VSG) gene expression sites (ESs), which are monoallelically expressed. Here, we use tandem affinity purification to determine the interacting partners of TbISWI. We identify three proteins that do not show significant homology with known ISWI-associated partners. Surprisingly, one of these is nucleoplasmin-like protein (NLP), which we had previously shown to play a role in ES control. In addition, we identify two novel ISWI partners, regulator of chromosome condensation 1-like protein (RCCP) and phenylalanine/tyrosine-rich protein (FYRP), both containing protein motifs typically found on chromatin proteins. Knockdown of RCCP or FYRP in bloodstream form T. brucei results in derepression of silent variant surface glycoprotein ESs, as had previously been shown for TbISWI and NLP. All four proteins are expressed and interact with each other in both major life cycle stages and show similar distributions at Pol I-transcribed loci. They are also found at Pol II strand switch regions as determined with ChIP. ISWI, NLP, RCCP, and FYRP therefore appear to form a single major ISWI complex in T. brucei (TbIC). This reduced complexity of ISWI regulation and the presence of novel ISWI partners highlights the early divergence of trypanosomes in evolution. American Society for Biochemistry and Molecular Biology 2015-11-06 2015-09-15 /pmc/articles/PMC4646403/ /pubmed/26378228 http://dx.doi.org/10.1074/jbc.M115.679019 Text en © 2015 by The American Society for Biochemistry and Molecular Biology, Inc. Author's Choice—Final version free via Creative Commons CC-BY license (http://creativecommons.org/licenses/by/4.0) .
spellingShingle Microbiology
Stanne, Tara
Narayanan, Mani Shankar
Ridewood, Sophie
Ling, Alexandra
Witmer, Kathrin
Kushwaha, Manish
Wiesler, Simone
Wickstead, Bill
Wood, Jennifer
Rudenko, Gloria
Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei
title Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei
title_full Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei
title_fullStr Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei
title_full_unstemmed Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei
title_short Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei
title_sort identification of the iswi chromatin remodeling complex of the early branching eukaryote trypanosoma brucei
topic Microbiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4646403/
https://www.ncbi.nlm.nih.gov/pubmed/26378228
http://dx.doi.org/10.1074/jbc.M115.679019
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