Cohesin regulation and roles in chromosome structure and function

Natalie L Rittenhouse1, Jill M Dowen2

  • 1Curriculum in Genetics & Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.

Summary

The cohesin complex forms DNA loops to regulate gene transcription. This review explores recent discoveries on cohesin

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Cohesins02:20

Cohesins

Cohesin protein complexes are a molecular glue that holds two sister chromatids together. They play an important role both in mitosis and meiosis. In mitosis, all cohesin complexes present on the chromosomes are removed before the start of the anaphase stage.
Cohesin complexes in Meiotic Division
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Separation of Sister Chromatids02:17

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At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
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Chromosome Structure02:40

Chromosome Structure

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Meiosis II02:02

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Meiosis II entails cell division and segregation of the sister chromatids, resulting in the production of four unique haploid gametes. The steps for meiosis II are similar to mitosis, except that meiosis II occurs in haploid cells, whereas mitosis occurs in diploid cells.
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