Vertebrate skeletal muscle contraction, also depends on set of specialized accessory proteins that are closely associated with the actin thin filaments:

a) Tropomyosin

b) Troponin

TLS Online TPP Program

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#XL - T Zoology

The ATPase domains interact with the proteins

Scc1 and Scc3, which together form a cohesin ring structure which embrace one or both copies of the replicated DNA.

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#Id: 8858

#XL - T Zoology

Cohesin-mediated cohesion between sister chromatids is established by a two-step process:

1.Loading and unloading of cohesins

2. Stabilization of cohesins

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#XL - T Zoology

During G1, 

cohesins associate with chromosomes by cohesin loading factors Scc2 and Scc4 and unloaded continuously by a cohesin associated complex Pds5 and Wap1 proteins. 

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#Id: 8860

#XL - T Zoology

During S phase

DNA-bound G1 cohesins Convert into cohesive complexes by cohesin acetyl transferases (CoATs)

which acetylate Smc3 subunit & prevents unloading of cohesins by Pds5-Wapl, thereby stabilizing the cohesins on chromosomes.

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#XL - T Zoology

In vertebrates, stabilization of cohesins requires the cohesin-associated factor sororin.

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#XL - T Zoology

Defects of cohesin’s gene expression regulation function are the cause of a group of diseases collectively called cohesinopathies.