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Real-time imaging of DNA loop extrusion by condensin.

ABSTRACT: It has been hypothesized that SMC protein complexes such as condensin and cohesin spatially organize chromosomes by extruding DNA into large loops. We directly visualized the formation and processive extension of DNA loops by yeast condensin in real time. Our findings constitute unambiguous evidence for loop extrusion. We observed that a single condensin complex is able to extrude tens of kilobase pairs of DNA at a force-dependent speed of up to 1500 base pairs per second, using the energy of adenosine triphosphate hydrolysis. Condensin-induced loop extrusion was strictly asymmetric, which demonstrates that condensin anchors onto DNA and reels it in from only one side. Active DNA loop extrusion by SMC complexes may provide the universal unifying principle for genome organization.

SUBMITTER: Ganji M

PROVIDER: S-EPMC6329450 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Real-time imaging of DNA loop extrusion by condensin.

Ganji Mahipal M Shaltiel Indra A IA Bisht Shveta S Kim Eugene E Kalichava Ana A Haering Christian H CH Dekker Cees C

Science (New York, N.Y.) 20180222 6384

It has been hypothesized that SMC protein complexes such as condensin and cohesin spatially organize chromosomes by extruding DNA into large loops. We directly visualized the formation and processive extension of DNA loops by yeast condensin in real time. Our findings constitute unambiguous evidence for loop extrusion. We observed that a single condensin complex is able to extrude tens of kilobase pairs of DNA at a force-dependent speed of up to 1500 base pairs per second, using the energy of ad ...[more]

PMID: 29472443

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Condensin complexes: understanding loop extrusion one conformational change at a time.

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2019-09-23 | GSE117854 | GEO

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Human cohesin compacts DNA by loop extrusion.

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