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Endothelial nitric oxide synthase ( eNOS ) is one of three enzymes capable of producing nitric oxide ( NO) . This molecule fully key functions in the cardiovascular system . ENOS gene consists of 26 exons and the fragment of chromosome 7 is about the size of 22 kb. Gene promoter does not contain a basic sequence recognized by a complex of RNA polymerase II preinicjacyjny , tzw.TATA box . Analysis of the region 5 revealed the presence of multiple potential binding sites for a number of additional transcription factors , suggesting the possibility of a complex and dynamic expression regulation . The gene of endothelial nitric oxide synthase has a significant polymorphism in the promoter region and in the introns as well as within the coding sequences. In order to demonstrate a statistically significant relationship between specific allelic variants and the various cardiovascular disorders have been numerous population-based analysis . Active form of the enzyme is a homodimer . Within the individual monomer divided into the following domains : the C- terminal domain of the reductase showing substantial amino acid sequence homology with reductase cytochrome P -450 , a small domain responsible for binding to calmodulin oxygenase domain and N- terminal fragment and being the site of myristylation palmitylacji . The enzyme contains relatively strongly associated cofactors FAD , FMN , tetrahydrobiopterynę ( BH4 ) and the heme moiety . FAD and FMN allow the flow of electrons between NADPH and heme , while the role of BH4 has not been finally clarified . ENOS activity is strictly dependent on the presence of a Ca2 + / calmodulin , which is bound to the enzyme abolishes the inhibitory effect of the insert located in the FMN binding . It is postulated that the direct product of the two-step oxidation reaction is arginine and citrulline nitric oxide . The source of electrons is NADPH . A detailed reaction mechanism is unknown. Despite advanced research, some of the important structural and functional characteristics of eNOS remain a mystery.
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Andrzej Łukaszyk - przewodniczący, Zofia Bielańska-Osuchowska, Szczepan Biliński, Mieczysław Chorąży, Aleksander Koj, Włodzimierz Korochoda, Leszek Kuźnicki, Aleksandra Stojałowska, Lech Wojtczak

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