# Modeling Meiotic Chromosomes Indicates a Size Dependent Contribution of Telomere Clustering and Chromosome Rigidity to Homologue Juxtaposition

Christopher A. Penfold, University of Cambridge
Paul E. Brown
Neil D. Lawrence, University of Sheffield
Alastair S. H. Goldman

PLoS Computat Biol 8, pp 0-0

#### Abstract

Meiosis is the cell division that halves the genetic component of diploid cells to form gametes or spores. To achieve this, meiotic cells undergo a radical spatial reorganisation of chromosomes. This reorganisation is a prerequisite for the pairing of parental homologous chromosomes and the reductional division, which halves the number of chromosomes in daughter cells. Of particular note is the change from a centromere clustered layout (Rabl configuration) to a telomere clustered conformation (bouquet stage). The contribution of the bouquet structure to homologous chromosome pairing is uncertain. We have developed a new in silico model to represent the chromosomes of Saccharomyces cerevisiae in space, based on a worm-like chain model constrained by attachment to the nuclear envelope and clustering forces. We have asked how these constraints could influence chromosome layout, with particular regard to the juxtaposition of homologous chromosomes and potential nonallelic, ectopic, interactions. The data support the view that the bouquet may be sufficient to bring short chromosomes together, but the contribution to long chromosomes is less. We also find that persistence length is critical to how much influence the bouquet structure could have, both on pairing of homologues and avoiding contacts with heterologues. This work represents an important development in computer modeling of chromosomes, and suggests new explanations for why elucidating the functional significance of the bouquet by genetics has been so difficult.

  @Article{penfold-meiotic12, title = {Modeling Meiotic Chromosomes Indicates a Size Dependent Contribution of Telomere Clustering and Chromosome Rigidity to Homologue Juxtaposition}, journal = {PLoS Computat Biol}, author = {Christopher A. Penfold and Paul E. Brown and Neil D. Lawrence and Alastair S. H. Goldman}, pages = {0}, year = {2012}, volume = {8}, number = {5}, month = {00}, edit = {https://github.com/lawrennd//publications/edit/gh-pages/_posts/2012-01-01-penfold-meiotic12.md}, url = {http://inverseprobability.com/publications/penfold-meiotic12.html}, abstract = {Meiosis is the cell division that halves the genetic component of diploid cells to form gametes or spores. To achieve this, meiotic cells undergo a radical spatial reorganisation of chromosomes. This reorganisation is a prerequisite for the pairing of parental homologous chromosomes and the reductional division, which halves the number of chromosomes in daughter cells. Of particular note is the change from a centromere clustered layout (Rabl configuration) to a telomere clustered conformation (bouquet stage). The contribution of the bouquet structure to homologous chromosome pairing is uncertain. We have developed a new in silico model to represent the chromosomes of Saccharomyces cerevisiae in space, based on a worm-like chain model constrained by attachment to the nuclear envelope and clustering forces. We have asked how these constraints could influence chromosome layout, with particular regard to the juxtaposition of homologous chromosomes and potential nonallelic, ectopic, interactions. The data support the view that the bouquet may be sufficient to bring short chromosomes together, but the contribution to long chromosomes is less. We also find that persistence length is critical to how much influence the bouquet structure could have, both on pairing of homologues and avoiding contacts with heterologues. This work represents an important development in computer modeling of chromosomes, and suggests new explanations for why elucidating the functional significance of the bouquet by genetics has been so difficult.}, key = {Penfold-meiotic12}, doi = {10.1371/journal.pcbi.1002496}, linkpdf = {http://www.ploscompbiol.org/article/fetchObjectAttachment.action;jsessionid=AC52AAF9AB8D2E1F9CF3399F6F8C2E3A?uri=info%3Adoi%2F10.1371%2Fjournal.pcbi.1002496&representation=PDF}, OPTgroup = {} }
 %T Modeling Meiotic Chromosomes Indicates a Size Dependent Contribution of Telomere Clustering and Chromosome Rigidity to Homologue Juxtaposition %A Christopher A. Penfold and Paul E. Brown and Neil D. Lawrence and Alastair S. H. Goldman %B %C PLoS Computat Biol %D %F penfold-meiotic12 %J PLoS Computat Biol %P 0--0 %R 10.1371/journal.pcbi.1002496 %U http://inverseprobability.com/publications/penfold-meiotic12.html %V 8 %N 5 %X Meiosis is the cell division that halves the genetic component of diploid cells to form gametes or spores. To achieve this, meiotic cells undergo a radical spatial reorganisation of chromosomes. This reorganisation is a prerequisite for the pairing of parental homologous chromosomes and the reductional division, which halves the number of chromosomes in daughter cells. Of particular note is the change from a centromere clustered layout (Rabl configuration) to a telomere clustered conformation (bouquet stage). The contribution of the bouquet structure to homologous chromosome pairing is uncertain. We have developed a new in silico model to represent the chromosomes of Saccharomyces cerevisiae in space, based on a worm-like chain model constrained by attachment to the nuclear envelope and clustering forces. We have asked how these constraints could influence chromosome layout, with particular regard to the juxtaposition of homologous chromosomes and potential nonallelic, ectopic, interactions. The data support the view that the bouquet may be sufficient to bring short chromosomes together, but the contribution to long chromosomes is less. We also find that persistence length is critical to how much influence the bouquet structure could have, both on pairing of homologues and avoiding contacts with heterologues. This work represents an important development in computer modeling of chromosomes, and suggests new explanations for why elucidating the functional significance of the bouquet by genetics has been so difficult. 
 TY - CPAPER TI - Modeling Meiotic Chromosomes Indicates a Size Dependent Contribution of Telomere Clustering and Chromosome Rigidity to Homologue Juxtaposition AU - Christopher A. Penfold AU - Paul E. Brown AU - Neil D. Lawrence AU - Alastair S. H. Goldman PY - 2012/01/01 DA - 2012/01/01 ID - penfold-meiotic12 SP - 0 EP - 0 DO - 10.1371/journal.pcbi.1002496 L1 - http://www.ploscompbiol.org/article/fetchObjectAttachment.action;jsessionid=AC52AAF9AB8D2E1F9CF3399F6F8C2E3A?uri=info%3Adoi%2F10.1371%2Fjournal.pcbi.1002496&representation=PDF UR - http://inverseprobability.com/publications/penfold-meiotic12.html AB - Meiosis is the cell division that halves the genetic component of diploid cells to form gametes or spores. To achieve this, meiotic cells undergo a radical spatial reorganisation of chromosomes. This reorganisation is a prerequisite for the pairing of parental homologous chromosomes and the reductional division, which halves the number of chromosomes in daughter cells. Of particular note is the change from a centromere clustered layout (Rabl configuration) to a telomere clustered conformation (bouquet stage). The contribution of the bouquet structure to homologous chromosome pairing is uncertain. We have developed a new in silico model to represent the chromosomes of Saccharomyces cerevisiae in space, based on a worm-like chain model constrained by attachment to the nuclear envelope and clustering forces. We have asked how these constraints could influence chromosome layout, with particular regard to the juxtaposition of homologous chromosomes and potential nonallelic, ectopic, interactions. The data support the view that the bouquet may be sufficient to bring short chromosomes together, but the contribution to long chromosomes is less. We also find that persistence length is critical to how much influence the bouquet structure could have, both on pairing of homologues and avoiding contacts with heterologues. This work represents an important development in computer modeling of chromosomes, and suggests new explanations for why elucidating the functional significance of the bouquet by genetics has been so difficult. ER - 
 Penfold, C.A., Brown, P.E., Lawrence, N.D. & Goldman, A.S.H.. (2012). Modeling Meiotic Chromosomes Indicates a Size Dependent Contribution of Telomere Clustering and Chromosome Rigidity to Homologue Juxtaposition. PLoS Computat Biol 8(5):0-0