Most common CFTR mutation is a ΔF508 -

Prevents normal transport of CFTR to the plasma membrane by blocking its packaging into COPII vesicles budding from the ER. 

Change the conformation of the cytosolic portion of CFTR so that the signal is unable to bind to Sec24.

TLS Online TPP Program

#Id: 8858

#Section 3: Genetics, Cellular and Molecular Biology

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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#Id: 8859

#Section 3: Genetics, Cellular and Molecular Biology

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. 

TLS Online TPP Program

#Id: 8860

#Section 3: Genetics, Cellular and Molecular Biology

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.

TLS Online TPP Program

#Id: 8862

#Section 3: Genetics, Cellular and Molecular Biology

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

TLS Online TPP Program

#Id: 8864

#Section 3: Genetics, Cellular and Molecular Biology

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

TLS Online TPP Program

#Id: 8865

#Section 3: Genetics, Cellular and Molecular Biology

The phosphorylation state of T14 and Y15 is controlled by a dual-specificity protein kinase known as Wee1 and a pair of dual-specificity phosphatases, Cdc25B and Cdc25C (Threonine 14 is not phosphorylated in S. pombe CDK1)