Histones and the mystery of cell proliferation
Before cells divide, they create so much genetic material that it must be wound onto spools before the two new cells can split apart. These spools are actually proteins called histones, and they must multiply at the same moment that the cell doubles its DNA. If the amount of histones does not increase when the DNA doubles, the centimeters of new DNA could never be packed small enough to fit into chromosomes, which are just a few micrometers long. In the early stage of development, the period when DNA doubles and the cell divides is called proliferation, after which an embryo grows from one cell to more than one thousand cells. Eventually, the new cells will differentiate into specific tissues. Even though cell proliferation is common in all tissue development, researchers do not fully understand how the amount of histone proteins increases in proportion to the amount of DNA during...