What keeps DNA from getting tangled?

One family of proteins — known as SMC — acts like a belay device used by rock climbers, which passes ropes through a series of loops. Their study is the first to explain how the two families of proteins keep DNA tangle-free under the confined, crowded conditions of the cell.

Why does a cell need to replicate its DNA What is it getting ready to do?

DNA replication is the process by which a double-stranded DNA molecule is copied to produce two identical DNA molecules. Replication is an essential process because, whenever a cell divides, the two new daughter cells must contain the same genetic information, or DNA, as the parent cell.

Why does DNA become a protein?

In the first step, the information in DNA is transferred to a messenger RNA (mRNA) molecule by way of a process called transcription. The mRNA sequence is thus used as a template to assemble—in order—the chain of amino acids that form a protein.

What is tangled DNA?

Proteins such as condensins bunch up the DNA. They aren’t the whole story, however, since protein-degrading enzymes don’t spur chromosomes to completely unravel. The DNA itself is tangled, and these knots might also help the chromosome stay taut, Kawamura et al. hypothesized.

What is the tangled structure of DNA?

It’s DNA, but not as we know it. In a world first, Australian researchers have identified a new DNA structure—called the i-motif—inside cells. A twisted ‘knot’ of DNA, the i-motif has never before been directly seen inside living cells.

How do cells ensure that DNA replication is accurate?

How do cells help ensure that DNA replication is accurate? The DNA Polymerase detects if there is an error, it removes the incorrect nucleotide and replaces it with the correct one.

How is mRNA formed?

The process of making mRNA from DNA is called transcription, and it occurs in the nucleus. The mRNA directs the synthesis of proteins, which occurs in the cytoplasm. mRNA formed in the nucleus is transported out of the nucleus and into the cytoplasm where it attaches to the ribosomes.

What prevents chromatin from becoming tangled?

The ringlike proteins, positioned at the base of each loop, create a central scaffolding from which the loops emanate, and the entire chromosome becomes shorter and stiffer. (Loop extrusion is also responsible for preventing duplicated chromosomes from becoming knotted and entangled, according to Mirny.

What prevents chromatin from becoming tangled during mitosis?

The complex task of packaging DNA is accomplished by specialized proteins that bind to and fold the DNA, generating a series of coils and loops that provide increasingly higher levels of organization, preventing the DNA from becoming an unmanageable tangle.