Histone acetyltransferase p300 also known as p300 HAT or E1A-associated protein p300 is an enzyme that, in humans, is encoded by the EP300 gene. It functions as histone acetyltransferase that regulates transcription of genes via chromatin remodeling by allowing histone proteins to wrap DNA less tightly. This enzyme plays an essential role in regulating cell growth and division, prompting cells to mature and assume specialized functions (differentiate), and preventing the growth of cancerous tumors. The p300 protein appears to be critical for normal development before and after birth. p300 HAT functions as histone acetyltransferase that regulates transcription via chromatin remodeling, and is important in the processes of cell proliferation and differentiation. It mediates cAMP-gene regulation by binding specifically to phosphorylated CREB protein. The p300 protein carries out its function of activating transcription by binding to transcription factors, and the transcription machinery. On the basis of this function, p300 is called a transcriptional coactivator. Mutations in the EP300 gene are responsible for a small percentage of cases of Rubinstein-Taybi syndrome. These mutations result in the loss of one copy of the gene in each cell, which reduces the amount of p300 protein by half. Some mutations lead to the production of a very short, nonfunctional version of the p300 protein, while others prevent one copy of the gene from making any protein at all. Although researchers do not know how a reduction in the amount of p300 protein leads to the specific features of Rubinstein-Taybi syndrome, it is clear that the loss of one copy of the EP300 gene disrupts normal development. Here you can see the structure of an human nucleosome in complex with the catalytic domain of p300 protein (yellow ribbons) (PDB code: 7W9V )
#moleculartart ... #immolecular ... #epigenetics ... #p300 ... #nucleosome ... #histone ... #acetyltransferase
Rendered with @proteinimaging and depicted with @corelphotopaint
#moleculartart ... #immolecular ... #epigenetics ... #p300 ... #nucleosome ... #histone ... #acetyltransferase
Rendered with @proteinimaging and depicted with @corelphotopaint
