Vitamins and minerals: nuclear receptor partner: practice question

A Biochemistry question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

Biochemistry · Vitamins and minerals: nuclear receptor partner

Sample item

The vitamin D receptor and the retinoic acid receptor both act on DNA only after pairing with a common partner, whereas oestrogen, glucocorticoid and androgen receptors act as homodimers. Which partner is it?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

D. Retinoid X receptor

The retinoid X receptor is the common heterodimer partner of the vitamin D, retinoic acid and thyroid hormone receptors. Steroid receptors bind DNA mainly as homodimers. This explains the overlap in the effects of vitamin A and vitamin D on gene expression.

Option by option

  • A. Oestrogen receptor

    The oestrogen receptor works as a homodimer.

  • B. Glucocorticoid receptor

    The glucocorticoid receptor works as a homodimer on its own response elements.

  • C. Androgen receptor

    The androgen receptor works as a homodimer.

  • D. Retinoid X receptor (correct)

    Correct. RXR forms heterodimers with the vitamin D and retinoic acid receptors.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More Biochemistry questions

Questions about this Biochemistry question

What is the answer to this Biochemistry question?

The best answer is D, Retinoid X receptor. The retinoid X receptor is the common heterodimer partner of the vitamin D, retinoic acid and thyroid hormone receptors.

Why is "Oestrogen receptor" not the answer?

The oestrogen receptor works as a homodimer.

Why is "Glucocorticoid receptor" not the answer?

The glucocorticoid receptor works as a homodimer on its own response elements.

Why is "Androgen receptor" not the answer?

The androgen receptor works as a homodimer.

What concept does this question test?

It tests Vitamins and minerals: nuclear receptor partner in Biochemistry. Steroid receptors bind DNA mainly as homodimers. This explains the overlap in the effects of vitamin A and vitamin D on gene expression.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Vitamins and minerals: nuclear receptor partner?

Build one table of enzyme deficiency, disease, inheritance and key finding, then revise it by spaced recall. Then use the flashcards and the other Biochemistry questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.