Following statements are regarding to the desensitization mechanism of GPCR.

A. Several residues in the cytosolic domain of the β-adrenergic receptor are phosphorylated by the enzyme rhodopsin kinase.

B. β-Arrestin binds to specific phosphorylated tyrosine residues in the C-terminal segment of G protein–coupled receptors (GPCRs).

C. Clathrin and AP2, two other proteins bound by β-arrestin, promote endocytosis of the receptor.

D. β-Arrestin also functions in transducing signals from activated receptors by binding to and activating several cytosolic protein kinases like Src activates the MAP kinase pathway, leading to phosphorylation of key transcription factor.

Which of the following combination is incorrect?

#Question id: 4489

#Unit 3. Fundamental Processes

HSP70 gene from Drosophila. This gene, activated by heat shock, is controlled by two activators GAGA binding factor and HSF,In response to heat shock, HSF binds to specific sites at the promoter and recruits a kinase, P-TEFb (positive transcription elongation factor). What is the proper mechanism of pausing and release of Pol II ?

#Question id: 4490

#Unit 3. Fundamental Processes

The human immunodeficiency virus (HIV), which causes AIDS, transcribes its genes from a promoter controlled by P-TEFb (and SEC). Again, polymerase initiates transcription at that promoter, under the control of which activator?

#Question id: 4491

#Unit 3. Fundamental Processes

HIV transcribes its genes from a promoter controlled by P-TEFb, P-TEFb is brought to the stalled polymerase by an RNA-binding protein, not a DNA-bound one. The protein responsible is called

#Question id: 4492

#Unit 3. Fundamental Processes

If an enhancer activates a specific gene 400 kb away, what stops it from activating other genes whose promoters are within that range?

#Question id: 4493

#Unit 3. Fundamental Processes

An insulator is placed between the enhancer and the promoter, When bound by insulator-binding protein CTCF,

#Question id: 4494

#Unit 3. Fundamental Processes

Propagation of certain repressing histone modifications over stretches of chromatin lies at the heart of a phenomenon is known,