Popis: |
In the nucleus the DNA is packed along with proteins into a dynamic structure called chromatin. During cell cycle the chromatin structure becomes a subject to various changes. During interphase chromatin structure becomes loose while shortly before cell division it undertakes the form of highly condensed mitotic chromosomes. Structure of chromatin influences significantly mode of gene expression and its pattern. DNA-binding proteins interacting within chromatin are also necessary during this process. To gain the access to the DNA binding factors, the chromatin has to be in a loosened form. As long as the structure of the chromatin is more condensed it creates a barrier for the DNA binding proteins. Therefore it becomes obvious that the remodeling of the chromatin structure is one of the important regulators of gene expression and that the enzymes, which execute remodeling, are of great importance. One of them is ATPase Smarca5, which belongs to the protein subfamily ISWI and which creates the catalytic subunit for several different ATP-dependent chromatin remodeling complexes. Mutations of members of those complexes disturb regulation of transcription and cellular differentiation. In some cases the incorrect function of these complexes can lead to cellular transformation into a tumours state. This... |