Mitochondrial Uncoupling Protein 1 (UCP1) Quiz

What is the main function of UCP1 in brown adipose tissue (BAT)?

• Regulate cytoplasmic lipid droplets

• Store long-chain fatty acids (LCFAs)

• Increase IMM conductance for H+

• Generate ATP

What activates UCP1 to increase the conductance of the inner mitochondrial membrane (IMM)?

• ATP

• GTP

• Long-chain fatty acids (LCFAs)

• GDP

What is the mechanism of UCP1 operation when activated by long-chain fatty acids (LCFAs)?

What is the effect of fatty-acid-free bovine serum albumin (BSA) and alpha-cyclodextrin (αCD) on the UCP1 current?

• Stabilize the current

• No effect on the current

• Activate the current

• Inhibit the current

What is the relationship between IUCP1 reversal potentials and H+ equilibrium potentials?

• They are equal

• They are unrelated

• They are inversely proportional

• They are directly proportional

What is the effect of pH on the UCP1 current?

• Current amplitude increases at lower pH values

• Current amplitude decreases at lower pH values

• Current amplitude is not affected by pH

• Current amplitude remains constant at different pH values

What is the effect of long-chain acyl-CoA on the UCP1 current?

• Stabilizes the current

• No effect on the current

• Inhibits the current

• Activates the current

What is the main difficulty in determining the mechanism of UCP1 operation?

• Lack of a direct method to study UCP1 transport activity

• Lack of available UCP1 inhibitors

• Lack of interest in UCP1 research

• Lack of understanding of UCP1 structure

What is the significance of using the patch-clamp technique in studying UCP1 currents?

• It allows for visualization of UCP1 structure at the atomic level

• It allows for direct measurement of UCP1 currents in the native IMM of BAT

• It provides a detailed analysis of UCP1 gene expression

• It helps in isolating UCP1 protein for biochemical studies

What is the conclusion about the mechanism of UCP1 operation based on the pH dependence of the UCP1 current?

• UCP1 operates as an ATP-dependent channel

• UCP1 operates as an LCFA anion/H+ symporter

• UCP1 operates as an OH– uniporter

• UCP1 operates as a simple H+ channel