Question

You have been assigned to identify a novel purified protein in your lab. You immediately notice this protein contains a polypeptide chain that transverses the membrane seven times and the transmembrane portion of the protein consist of alpha helices. What can you conclude about this protein?

A) It belongs to the family of G-protein coupled receptors
B) It belong to the cyclin dependent kinase family
C) It belongs to the receptor tyrosine kinase family
D) It belongs to the enzyme-coupled receptors family
E) It belongs to the integrin family of cell membrane proteins

Answer 1

The protein described belongs to the G-protein coupled receptors family, which are involved in signal transduction across the cell membrane.

Step-by-step explanation:

The protein described in the question, with a polypeptide chain that transverses the membrane seven times and consists of alpha helices, belongs to the G-protein coupled receptors family.

G-protein linked receptors have seven transmembrane domains and bind a ligand to activate a G-protein, which then interacts with ion channels or enzymes in the membrane. These receptors play a role in signal transduction across the cell membrane.