Circular DNA molecules purified from both bacteria and eukaryotes are usually negatively supercoiled, having values of s of approximately –0.06.

TLS Online TPP Program

#Id: 10485

#Unit 4. Cell Communication and Cell Signaling

Phosphorylation of p53 on a serine residue in the N-terminus by ATM or DNA-PK displaces bound MDM2 from p53, thereby stabilizing it

TLS Online TPP Program

#Id: 10486

#Unit 4. Cell Communication and Cell Signaling

MDM2 levels in the cytoplasm are controlled by

ATR and p14ARF (p19ARF in the mouse), sequesters it in the nucleolus, where it cannot access p53.

TLS Online TPP Program

#Id: 10487

#Unit 4. Cell Communication and Cell Signaling

Neoantigens are self-antigens generated by tumor cells because of genomic mutations, also derive from unique proteins or peptides produced by dysregulated RNA splicing and disordered post-translational protein modification

TLS Online TPP Program

#Id: 10488

#Unit 4. Cell Communication and Cell Signaling

Most tumor cells,express MHC class I molecules on their surface, cytotoxic T cells can directly recognize tumor cells expressing neo-antigens.

TLS Online TPP Program

#Id: 10489

#Unit 4. Cell Communication and Cell Signaling

Cytotoxic T cells release granules containing the proteins perforin and granzyme-B

TLS Online TPP Program

#Id: 10490

#Unit 4. Cell Communication and Cell Signaling

perforins punch holes in the endocytic vesicle membrane, allowing granzymes to enter the cytoplasm