In small hypernating animals the inner mitochondrial membran

In small hypernating animals, the inner mitochondrial membrane of brown adipocytes are enriched in transmembrane proteins of the UCP family. In the mitochondria of these cells, ATP production is low, but oxygen consumption is similar to other cell types. Which of the statements below provides the most likely explanation for the function of the UCP proteins?

a. UCPs block the electron transfer chain

b. UCPs block cytochrome c motility inside the membrane

c. UCPs make the inner mito membrane permeable to protons

d. UCPs block the pyruvate transporter

e. UCPs block ATP synthase

Solution

c. UCPs make the inner mito membrane permeable to protons

Uncoupling protein (UCP) found in the inner mitochondrial membrane of brown adipocytes dissipates oxidative energy into heat by transporting protons from the cytosol into the mitochondrial matrix