A mysterious sheath-like structure occupies 47% of the part of each chromosome

Chromosomes contain not only more than 25,000 genes. Scientists found that a mysterious sheath-like structure occupies 47% of the part of each chromosome through recombinant mouse proteins. After modeling the length, width, surface area, volume, and DNA density of all normal human chromosomes, researchers found something important to our understanding of the internal structure of the chromosome. "Defining all 46 chromosomes in humans forces us to reconsider the idea that chromosomes are composed almost entirely of chromatin," said biologist Daniel Booth. "This assumption has never been challenged in 100 years." In their analysis, Chromatin accounts for only 53 to 70 percent of all chromosomal components.

Another structure, called the periphery of chromosomes, accounts for 30 to 47 percent of chromosomes, which researchers have observed in the past but don't know how much they are. This means that for any chromosome, DNA and its supporting protein may account for only half of all components. "The first application of 3D-CLEM analysis has produced a remarkable and surprising conclusion that a large part of the total volume of the mitotic chromosome is not composed of chromatin, but rather consists of the periphery of the chromosome," they wrote in the paper.

At this stage, people still don't understand what the specific function of this structure is, but the researchers suspected that its function may be some kinds of "sheath" so that chromosomes are separated from each other in cell division. This has also been supported by previous studies that have shown that this structure is partly due to the Ki-67 protein. Ki-67 is a marker of cell proliferation and binds to the chromosomal surface to isolate sister chromatids. If this is really the function of the chromosomal sheath, it means that this structure plays an important role in preventing the occurrence of an error in cell division.

In addition to its function, there are many things we don't know about this mysterious structure. We don't know whether it works as a liquid or solid film and how it affects the structural changes of chromatin during cell division. Therefore, it appears to be returning to the most basic cellular makeup problem.

"Now we have to rethink how chromosomes are constructed and how they are separated when they divide, because they are covered by other materials," said research team member Bill Earnshaw. This research paper has been published in the journal Molecular Cell. Flarebio provides you with superior recombinant proteins like recombinant PIGR at competitive prices.