Two major classes of actin-nucleating proteins:

1. Formins nucleate the assembly of unbranched filaments 

2. Arp2/3 complex nucleates the assembly of branched actin networks

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#Section 3: Genetics, Cellular and Molecular Biology

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

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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.

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#Section 3: Genetics, Cellular and Molecular Biology

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

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#Section 3: Genetics, Cellular and Molecular Biology

Autophagy can be either

• Nonselective autophagy

• Selective autophagy

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#Id: 8213

#Section 3: Genetics, Cellular and Molecular Biology

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

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