It is known that the mammary gland epithelial cells lining the immature ductules

Question

It is known that the mammary gland epithelial cells lining the immature ductules of the mammary gland is induced to differentiate into acinar cells and to produce milk proteins secreted into the mammary gland ducts during pregnancy. This induction process is initiated by the binding of prolactin to a receptor residing on the membrane of the mammary gland epithelial cells. (i) Please design an experiment to demonstrate the presence of such receptors residing on the membrane of the mammary gland epithelial cells? (ii). Please design a strategy for the purification of these receptor molecules. (iii). How will you confirm that the receptor molecules you have purified is the real prolactin receptor?

Explanation / Answer

i) If radioactive prolactin is introduced into circulation of human / rat; then it is found on the mammary gland epithelial cells, and thereafter in milk after some time. This indicates that this radioactive prolactin molecule binds to some other molecule on the surface of mammary gland epithelial cells, which are actually receptors of prolactin molecule.

ii) By using PCR , these receptor molecules can be isolated. Actually, receptors are also proteins; whose gene is present in the genome. If we find out the primer sequence of these receptor protein genes, then these can be desined in the laboratory.

No general method exists for isolation of proteins from tissues or organs. If it is necessary to determine the amount of protein in a mixture of animal foodstuffs, a sample is converted to ammonium salts by boiling with sulfuric acid and a suitable inorganic catalyst, such as copper sulfate (Kjeldahl method). The method is based on the assumption that proteins contain 16 percent nitrogen, and that nonprotein nitrogen is present in very small amounts.

In the above mentioned experiment, epithelial cells of rat mammary glands can be taken, and the amount of radioactive protein can be determined.

iii) Already , the receptor is showing radioactivity; thus is the real prolacting receptor; for that prolactin which was introduced in circulation.

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.