COP1 is found in the nucleus in the dark and in the cytoplasm in the light. COP1 movement into the nucleus in the dark requires the COP9 signalosome (CSN) complex

TLS Online TPP Program

#Id: 9929

#Unit 4. Cell Communication and Cell Signaling

TLS Online TPP Program

#Id: 9930

#Unit 4. Cell Communication and Cell Signaling

Variation in Influenza Strains

Antigenic variation in HA and NA is generated by

Antigenic drift involves a series of spontaneous point mutations that occur gradually.

Antigenic shift results in the sudden emergence of a new subtype of influenza.

TLS Online TPP Program

#Id: 9931

#Unit 4. Cell Communication and Cell Signaling

Original antigenic sin

Tendency to focus an immune attack on those structures that were present during the original.

This means that our immune systems effectively ignore the subtle changes occurring each year in pathogens

TLS Online TPP Program

#Id: 9932

#Unit 4. Cell Communication and Cell Signaling

TLS Online TPP Program

#Id: 9933

#Unit 4. Cell Communication and Cell Signaling

Bacterial Infections

Bacteria enter the body through several natural routes.

TLS Online TPP Program

#Id: 9934

#Unit 4. Cell Communication and Cell Signaling

Cell wall endotoxins of some gram-negative bacteria activate macrophages, resulting in release of high levels of IL-1 and TNF-α, which can cause septic shock.