S phase cyclin-CDK accumulates in late G1 , they are immediately inactivated by binding of a CKI called Sic1

TLS Online TPP Program

#Id: 8221

#Unit 2. Cellular Organization

The M6P receptor protein binds to M6P at pH 6.5–6.7 in the TGN lumen and releases it at pH 6, in the lumen of endosomes.

TLS Online TPP Program

#Id: 8223

#Unit 2. Cellular Organization

Retromer

a coat protein complex specialized for endosome-to-TGN transport, recycle the M6P receptor to the TGN

TLS Online TPP Program

#Id: 8224

#Unit 2. Cellular Organization

Lysosomal storage diseases:

• Hurler’s disease

• Inclusion-cell disease

TLS Online TPP Program

#Id: 8225

#Unit 2. Cellular Organization

Hurler’s disease- mutation in a structural gene that codes for an individual lysosomal hydrolase.

TLS Online TPP Program

#Id: 8226

#Unit 2. Cellular Organization

I-cell disease

• almost all of the hydrolytic enzymes are missing from the lysosomes of many cell types.

• mis-sorting has been traced to a defective or missing GlcNAc phosphotransferase.

TLS Online TPP Program

#Id: 8311

#Unit 2. Cellular Organization

Actin,

basic building block of microfilaments extraordinarily well conserved among eukaryotes.