N binds to RNA transcribed from DNA containing a nut sequence. Thus, once RNA polymerase has passed a nut site, N binds to the RNA and from there is loaded on to the polymerase itself. In this state, the polymerase is resistant to the terminators found just beyond the N and cro genes. 

TLS Online TPP Program

#Id: 1481

#Unit 4. Cell Communication and Cell Signaling

Let-7 miRNAs down-regulate the translation of Ras. Thus in the absence of the miRNAs, Ras is constitutively overproduced, contributing to tumorigenesis.

TLS Online TPP Program

#Id: 1482

#Unit 4. Cell Communication and Cell Signaling

Neurofibromatosis, a benign tumor of the sheath cells that surround nerves, is caused by loss of both alleles of NF1, which encodes a RAS GAP-type protein.

TLS Online TPP Program

#Id: 1483

#Unit 4. Cell Communication and Cell Signaling

MYC is translocated close to an antibody gene, leading to overproduction of MYC IN Burkitt’s Lymphoma due to translocation from Chromosome 8 to 14.

TLS Online TPP Program

#Id: 1484

#Unit 4. Cell Communication and Cell Signaling

Monomers and dimers of p53, exists in the cytoplasm. 

TLS Online TPP Program

#Id: 1485

#Unit 4. Cell Communication and Cell Signaling

The tetramerized p53 localize in nucleus for transcriptional activation.

TLS Online TPP Program

#Id: 1486

#Unit 4. Cell Communication and Cell Signaling

When DNA is damaged, p53 is tetramerized and accumulates rapidly.