Search results
Results from the WOW.Com Content Network
Usually, DNA condensation is defined as "the collapse of extended DNA chains into compact, orderly particles containing only one or a few molecules". [3] This definition applies to many situations in vitro and is also close to the definition of DNA condensation in bacteria as "adoption of relatively concentrated, compact state occupying a ...
Thus, acetylation of histones is known to increase the expression of genes through transcription activation. Deacetylation performed by HDAC molecules has the opposite effect. By deacetylating the histone tails, the DNA becomes more tightly wrapped around the histone cores, making it harder for transcription factors to bind to the DNA.
Single molecule studies have shown that Dps-DNA complexes can get trapped in long-lived metastable states that exhibit hysteresis. [12] Because of this, the extent of DNA condensation by Dps can depend not only on the current buffer conditions but also on the conditions in the past. A modified Ising model can be used to explain this binding ...
Magnetic tweezers experiments show that this non-specific binding of Fis can contribute to DNA condensation and organization. [81] [82] Fis causes mild condensation of a single DNA molecule at <1 mM, but induces substantial folding through the formation of DNA loops of an average size of ~800 bp at >1 mM. The loops in magnetic tweezers ...
In biology the term 'condensation' is used much more broadly and can also refer to liquid–liquid phase separation to form colloidal emulsions or liquid crystals within cells, and liquid–solid phase separation to form gels, [1] sols, or suspensions within cells as well as liquid-to-solid phase transitions such as DNA condensation during ...
Early single-DNA-molecule experiments also demonstrated in real time that condensin I is able to compact DNA in an ATP-hydrolysis dependent manner. [ 41 ] Most recently, single-molecule experiments have demonstrated that budding yeast condensin I is able to translocate along dsDNA ( motor activity) [ 42 ] and to "extrude" DNA loops ( loop ...
Such modifications affect the binding affinity between histones and DNA, and thus loosening or tightening the condensed DNA wrapped around histones, e.g., Methylation of specific lysine residues in H3 and H4 causes further condensation of DNA around histones, and thereby prevents binding of transcription factors to the DNA that lead to gene ...
The lack of 32 P-labeled DNA remaining in the solution after the bacteriophages had been allowed to adsorb to the bacteria showed that the phage DNA was transferred into the bacterial cell. The presence of almost all the radioactive 35 S in the solution showed that the protein coat that protects the DNA before adsorption stayed outside the cell.