The United States has developed a high-definition 4D map of the genome folding into a ring-shaped structure within the nucleus of a cell.

The latest issue of Cell magazine features on the cover of a joint team of researchers at Baylor College of Medicine, Rice University, Stanford University, and the Broad Institute: They created high-definition 4D maps of genomes folded into ringed structures in the nucleus of cells.
new research will help scientists take a fresh look at genetic diseases such as cancer by dynamically tracking the ring folding of complete genomes over time.
For decades, scientists have speculated that when human cells are stimulated, DNA (deoxyriucleic acid) elements in their nuclei quickly find distant pairs, forming different rings along chromosomes, and that by re-layout in space, cells can alter gene activity and thus regulate cell function.
but DNA rings have long been a blind spot in modern biology, and while it is known that DNA can form rings in cells, determining the exact location of these ring structures has been an unsto complete challenge.
until 2014, the joint research team made a complete difference.
they succeeded in mapping the human genome in unprecedented detail on how it folds into rings, and demonstrated that humans and other mammals, such as mice, are not only highly similar in one-dimensional genome sequences, but also have similar three-dimensional genome folding.
but these maps can only reflect a static state of the ring structure, can not observe the dynamic change of the ring structure process.
latest study, the team produced the first 4D HD video of DNA rings in the human genome and shed light on the unique mechanisms associated with ring location.
By destroying Cohesin, a ring protein complex found in almost all ring structures, they found the extrusion mechanism that controls the DNA ring: the adhesion protein is like a strap adjustment buckle for a shoulder bag, and by transporting a unilateral strap, the adjustment buckle allows the strap to form a ring to adjust the length of the strap, and the adhesive protein regulates the formation of the DNA ring like a regulatory buckle.
By looking closely at the video map, the researchers also found another blocking mechanism unrelated to adhesion proteins, unlike the extrusion mechanism, which allows DNA to form a ring-like structure along the same chromosome through two elements, which allows elements on different chromosomes to bind to a ring-like structure in the form of large atomic groups.
, the researchers say, these mechanisms can regulate the formation and disintegration of DNA rings to better understand cellular functions based on these folding structures.
source: Science and Technology Daily.