The DNA Damage Response | Repair the DNA or Commit Apoptosis?

[@stevenshivers6082]

Correction to your video: Succintly, phosphorylated retina blastoma renders dissociation from E2F. Subsequently, E2F can translocate to the nucleus to confer increased expression of E2F target genes, including E2F (positive feedback loop) and cyclin E to propogate entry into S-phase. CDK = Cyclin-Dependent-Kinase. Per definition, kinases phosphorylate (add phosphor groups to) targets. Thus, CDK will phosphorylate retina blastoma to confer its dissociation from E2F.

[@kalyanRanjit-u4z]

Yes the CDK2/Cyclin E phosphorylates PrB, which can release the factors that allow G1 to S.

[@AnchaliJunn]

Very nice explanation 😺

[@reezis1619]

doesn't the retinoblastic protein release E2F after phosphorylation?

[@jonathanlehmann2059]

I thought so too. From ‘Signal Transduction, Principles, Pathways, and Processes’, page 141: “Phosphorylation of the pRB family proteins by CDKs during G1 phase causes pRB to dissociate from E2Fs, allowing transcription of target genes that stimulate progression into S phase.”

[@reezis1619]

@@jonathanlehmann2059 Yeah. That is what it says in my textbook as well

[@jonathanlehmann2059]

milk is cheap protein Good to know, thanks. Mine is a 2013 book, so it’s possible that the field has changed since then, maybe.

[@sudiptasarma]

nicely explained.

[@alhaeri1]

in my opinion it should be more like high degredation of p53 in the case of low stress and low degredation of p53 in the case of high stress

[@dontmissthelittlethings]

Thanks for the information.

[@killianpapail9324]

Isn't the cdk4/6-cyclinD complex which phosphorylates Rb to release E2F ?

[@fatahiyakashif8199]

pRb is inactivated when phosphorylated and then it releases E2F which enters the nucleus and acts as a transcription factor for proteins that help in G1 to S phase transition.

[@seanclark6438]

Just double checking but is P21 negative my regulated by MDM2

[@fayazferoz7978]

it is p53 that is degraded by the action of MDM2

[@seanclark6438]

Fayaz Feroz Thanks couldn’t quite remember, when revising this I looked up all the gene loci, thanks to the wink wink to revise p53 and non of it came up on the exam

[@jamesbourke6211]

king