Limits of Chromosome Compaction by Loop-Extruding Motors
During mitosis, human chromosomes are linearly compacted about 1000-fold by loop-extruding motors. Recent experiments have shown that condensins extrude DNA loops but in a “one-sided” manner. This contrasts with existing models, which predict that symmetric, “two-sided” loop extrusion accounts for m...
| Main Authors: | , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
American Physical Society (APS)
2020
|
| Online Access: | https://hdl.handle.net/1721.1/126349 |
| _version_ | 1826201241146884096 |
|---|---|
| author | Banigan, Edward J Mirny, Leonid A |
| author2 | Massachusetts Institute of Technology. Institute for Medical Engineering & Science |
| author_facet | Massachusetts Institute of Technology. Institute for Medical Engineering & Science Banigan, Edward J Mirny, Leonid A |
| author_sort | Banigan, Edward J |
| collection | MIT |
| description | During mitosis, human chromosomes are linearly compacted about 1000-fold by loop-extruding motors. Recent experiments have shown that condensins extrude DNA loops but in a “one-sided” manner. This contrasts with existing models, which predict that symmetric, “two-sided” loop extrusion accounts for mitotic chromosome compaction. We explore whether one-sided extrusion, as it is currently seen in experiments, can compact chromosomes by developing a mean-field theoretical model for polymer compaction by motors that actively extrude loops and dynamically turnover. The model establishes a stringent upper bound of only about tenfold for compaction by strictly one-sided extrusion. We confirm this result with stochastic simulations. Thus, strictly one-sided extrusion as it has been observed so far cannot be the sole mechanism of chromosome compaction. However, as shown by the model, other two-sided or effectively two-sided mechanisms can achieve sufficient compaction. |
| first_indexed | 2024-09-23T11:48:29Z |
| format | Article |
| id | mit-1721.1/126349 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T11:48:29Z |
| publishDate | 2020 |
| publisher | American Physical Society (APS) |
| record_format | dspace |
| spelling | mit-1721.1/1263492022-10-01T06:12:24Z Limits of Chromosome Compaction by Loop-Extruding Motors Banigan, Edward J Mirny, Leonid A Massachusetts Institute of Technology. Institute for Medical Engineering & Science Massachusetts Institute of Technology. Department of Physics During mitosis, human chromosomes are linearly compacted about 1000-fold by loop-extruding motors. Recent experiments have shown that condensins extrude DNA loops but in a “one-sided” manner. This contrasts with existing models, which predict that symmetric, “two-sided” loop extrusion accounts for mitotic chromosome compaction. We explore whether one-sided extrusion, as it is currently seen in experiments, can compact chromosomes by developing a mean-field theoretical model for polymer compaction by motors that actively extrude loops and dynamically turnover. The model establishes a stringent upper bound of only about tenfold for compaction by strictly one-sided extrusion. We confirm this result with stochastic simulations. Thus, strictly one-sided extrusion as it has been observed so far cannot be the sole mechanism of chromosome compaction. However, as shown by the model, other two-sided or effectively two-sided mechanisms can achieve sufficient compaction. NSF Physics of Living Systems (Grant 15049420) National Institutes of Health (Grant GM114190) National Institutes of Health (Grant DK107980) 2020-07-23T16:11:02Z 2020-07-23T16:11:02Z 2019-07 2019-02 2019-10-09T16:56:52Z Article http://purl.org/eprint/type/JournalArticle 2160-3308 https://hdl.handle.net/1721.1/126349 Banigan, Edward J. and Leonid A. Mirny. "Limits of Chromosome Compaction by Loop-Extruding Motors." Physical Review X 9, 3 (July 2019): 031007 en 10.1103/physrevx.9.031007 Physical Review X Creative Commons Attribution 4.0 International license https://creativecommons.org/licenses/by/4.0/ application/pdf American Physical Society (APS) APS |
| spellingShingle | Banigan, Edward J Mirny, Leonid A Limits of Chromosome Compaction by Loop-Extruding Motors |
| title | Limits of Chromosome Compaction by Loop-Extruding Motors |
| title_full | Limits of Chromosome Compaction by Loop-Extruding Motors |
| title_fullStr | Limits of Chromosome Compaction by Loop-Extruding Motors |
| title_full_unstemmed | Limits of Chromosome Compaction by Loop-Extruding Motors |
| title_short | Limits of Chromosome Compaction by Loop-Extruding Motors |
| title_sort | limits of chromosome compaction by loop extruding motors |
| url | https://hdl.handle.net/1721.1/126349 |
| work_keys_str_mv | AT baniganedwardj limitsofchromosomecompactionbyloopextrudingmotors AT mirnyleonida limitsofchromosomecompactionbyloopextrudingmotors |