3 or 4 cGMP molecules must bind to each channel in order to open it; because of this cooperative allosteric interaction, channel opening is very sensitive to small changes in cGMP levels.

TLS Online TPP Program

#Id: 8219

#XL - Q Biochemistry

M6P residues are generated in the cis-Golgi by two Golgi-resident enzymes. 

1. N-acetylglucosamine (GlcNAc) phosphotransferase
2. Phosphodiesterase

TLS Online TPP Program

#Id: 8218

#XL - Q Biochemistry

Sorting signal that directs lysosomal hydrolases from the TGN to the late endosome is- Mannose 6-phosphate (M6P).

TLS Online TPP Program

#Id: 8217

#XL - Q Biochemistry

In selective autophagy

specific cargo is packaged into autophagosomes that tend to contain little cytosol, mediates the degradation of worn out, or unwanted, mitochondria, peroxisomes, ribosomes, and ER; used to destroy invading microbes.

TLS Online TPP Program

#Id: 8216

#XL - Q Biochemistry

In nonselective autophagy, a bulk portion of cytoplasm is sequestered in autophagosomes

TLS Online TPP Program

#Id: 8215

#XL - Q Biochemistry

Autophagy can be either

• Nonselective autophagy

• Selective autophagy

TLS Online TPP Program

#Id: 8213

#XL - Q Biochemistry

Autophagy occurs in the following sequence of steps:

Induction by activation of mTOR complex 1

• Nucleation of autophagosome formation by ATG9

• Closure of the membrane cup to form autophagosome

• Fusion of the autophagosome with lysosomes, catalyzed by SNAREs.

• Digestion of the inner membrane and the lumenal contents of the autophagosome