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Partitioning of the 2-μm Circle Plasmid of Saccharomyces cerevisiae : Functional Coordination with Chromosome Segregation and Plasmid-Encoded Rep Protein Distribution
The efficient partitioning of the 2-μm plasmid of Saccharomyces cerevisiae at cell division is dependent on two plasmid-encoded proteins (Rep1p and Rep2p), together with the cis-acting locus REP3 (STB). In addition, host encoded factors are likely to contribute to plasmid segregation. Direct observa...
Autores principales: | , , , , |
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Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
2000
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2174858/ https://www.ncbi.nlm.nih.gov/pubmed/10791970 |
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author | Velmurugan, Soundarapandian Yang, Xian-Mei Chan, Clarence S.-M. Dobson, Melanie Jayaram, Makkuni |
author_facet | Velmurugan, Soundarapandian Yang, Xian-Mei Chan, Clarence S.-M. Dobson, Melanie Jayaram, Makkuni |
author_sort | Velmurugan, Soundarapandian |
collection | PubMed |
description | The efficient partitioning of the 2-μm plasmid of Saccharomyces cerevisiae at cell division is dependent on two plasmid-encoded proteins (Rep1p and Rep2p), together with the cis-acting locus REP3 (STB). In addition, host encoded factors are likely to contribute to plasmid segregation. Direct observation of a 2-μm–derived plasmid in live yeast cells indicates that the multiple plasmid copies are located in the nucleus, predominantly in clusters with characteristic shapes. Comparison to a single-tagged chromosome or to a yeast centromeric plasmid shows that the segregation kinetics of the 2-μm plasmid and the chromosome are quite similar during the yeast cell cycle. Immunofluorescence analysis reveals that the plasmid is colocalized with the Rep1 and Rep2 proteins within the yeast nucleus. Furthermore, the Rep proteins (and therefore the plasmid) tend to concentrate near the poles of the yeast mitotic spindle. Depolymerization of the spindle results in partial dispersion of the Rep proteins in the nucleus concomitant with a loosening in the association between plasmid molecules. In an ipl1-2 yeast strain, shifted to the nonpermissive temperature, the chromosomes and plasmid almost always missegregate in tandem. Our results suggest that, after DNA replication, plasmid distribution to the daughter cells occurs in the form of specific DNA-protein aggregates. They further indicate that the plasmid partitioning mechanism may exploit at least some of the components of the cellular machinery required for chromosomal segregation. |
format | Text |
id | pubmed-2174858 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2000 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21748582008-05-01 Partitioning of the 2-μm Circle Plasmid of Saccharomyces cerevisiae : Functional Coordination with Chromosome Segregation and Plasmid-Encoded Rep Protein Distribution Velmurugan, Soundarapandian Yang, Xian-Mei Chan, Clarence S.-M. Dobson, Melanie Jayaram, Makkuni J Cell Biol Original Article The efficient partitioning of the 2-μm plasmid of Saccharomyces cerevisiae at cell division is dependent on two plasmid-encoded proteins (Rep1p and Rep2p), together with the cis-acting locus REP3 (STB). In addition, host encoded factors are likely to contribute to plasmid segregation. Direct observation of a 2-μm–derived plasmid in live yeast cells indicates that the multiple plasmid copies are located in the nucleus, predominantly in clusters with characteristic shapes. Comparison to a single-tagged chromosome or to a yeast centromeric plasmid shows that the segregation kinetics of the 2-μm plasmid and the chromosome are quite similar during the yeast cell cycle. Immunofluorescence analysis reveals that the plasmid is colocalized with the Rep1 and Rep2 proteins within the yeast nucleus. Furthermore, the Rep proteins (and therefore the plasmid) tend to concentrate near the poles of the yeast mitotic spindle. Depolymerization of the spindle results in partial dispersion of the Rep proteins in the nucleus concomitant with a loosening in the association between plasmid molecules. In an ipl1-2 yeast strain, shifted to the nonpermissive temperature, the chromosomes and plasmid almost always missegregate in tandem. Our results suggest that, after DNA replication, plasmid distribution to the daughter cells occurs in the form of specific DNA-protein aggregates. They further indicate that the plasmid partitioning mechanism may exploit at least some of the components of the cellular machinery required for chromosomal segregation. The Rockefeller University Press 2000-05-01 /pmc/articles/PMC2174858/ /pubmed/10791970 Text en © 2000 The Rockefeller University Press This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Original Article Velmurugan, Soundarapandian Yang, Xian-Mei Chan, Clarence S.-M. Dobson, Melanie Jayaram, Makkuni Partitioning of the 2-μm Circle Plasmid of Saccharomyces cerevisiae : Functional Coordination with Chromosome Segregation and Plasmid-Encoded Rep Protein Distribution |
title | Partitioning of the 2-μm Circle Plasmid of Saccharomyces cerevisiae
: Functional Coordination with Chromosome Segregation and Plasmid-Encoded Rep Protein Distribution |
title_full | Partitioning of the 2-μm Circle Plasmid of Saccharomyces cerevisiae
: Functional Coordination with Chromosome Segregation and Plasmid-Encoded Rep Protein Distribution |
title_fullStr | Partitioning of the 2-μm Circle Plasmid of Saccharomyces cerevisiae
: Functional Coordination with Chromosome Segregation and Plasmid-Encoded Rep Protein Distribution |
title_full_unstemmed | Partitioning of the 2-μm Circle Plasmid of Saccharomyces cerevisiae
: Functional Coordination with Chromosome Segregation and Plasmid-Encoded Rep Protein Distribution |
title_short | Partitioning of the 2-μm Circle Plasmid of Saccharomyces cerevisiae
: Functional Coordination with Chromosome Segregation and Plasmid-Encoded Rep Protein Distribution |
title_sort | partitioning of the 2-μm circle plasmid of saccharomyces cerevisiae
: functional coordination with chromosome segregation and plasmid-encoded rep protein distribution |
topic | Original Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2174858/ https://www.ncbi.nlm.nih.gov/pubmed/10791970 |
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