β-Carotene is the precursor of vitamin A1.
Oxidation at C-15 converts retinol to the aldehyde, retinal, and further oxidation produces retinoic acid, a hormone that regulates gene expression. 

TLS Online TPP Program

#Id: 8127

#XL - T Zoology

β-Carotene is the precursor of vitamin A1.
Oxidation at C-15 converts retinol to the aldehyde, retinal, and further oxidation produces retinoic acid, a hormone that regulates gene expression. 

TLS Online TPP Program

#Id: 8152

#XL - Q Biochemistry

After the vesicle coat is complete, the Sec23 coat subunit promotes GTP hydrolysis causes disassembly of the coat.

TLS Online TPP Program

#Id: 8153

#XL - Q Biochemistry

A second function of small GTPases in vesicle formation is in the pinching off of a completed vesicle from the parent membrane

TLS Online TPP Program

#Id: 8154

#XL - Q Biochemistry

Sar1 GTPase drives the pinching off of COPII vesicles

ARF GTPase drives the pinching off of COPIvesicles

Dynamin GTPase drives the pinching off of clathrin-coated vesicles

TLS Online TPP Program

#Id: 8156

#XL - Q Biochemistry

Two different kinds of sorting signals:

Membrane cargo proteins carry cytoplasmic sorting signals

Soluble cargo proteins carry luminal sorting signals

TLS Online TPP Program

#Id: 8157

#XL - Q Biochemistry

TLS Online TPP Program

#Id: 8158

#XL - Q Biochemistry

Soluble ER-resident proteins contain C-terminal KDEL sorting signal that allows them to be retrieved.