Question

DNA found in the nucleus is wrapped around a simple protein which is basic in nature. This protein is also thought to regulate DNA functioning find some way. Name this protein.

• A. Collagen
• B. Renin
• C. Pepsin
• D. Histones

Answer 1

The correct option is D Histones

Histones are the major structural proteins of chromosomes. The DNA molecule is wrapped twice around a Histone Octamer to make a Nucleosome. Six Nucleosomes are assembled into a Solenoid in association with H1 histones. The solenoids are in turn coiled onto a Scaffold, which is further coiled to make the chromosomal matrix. A unit in which a molecule of a histone is bound to a segment of the DNA chain of genetic material is termed a nucleosome. It has been suggested that changes in these units are associated with changes in the physical state and function of the chromatin during cell division and the transcription of the genetic message. Discovered in avian red blood cell nuclei by Albrecht Kossel about 1884, histones are water-soluble and contain large amounts of basic amino acids, particularly lysine and arginine. They are abundant in the thymus and pancreas.

So the correct option is 'histones'.