At an activation stage the first echelon cage life still can be kept. There are regulators which block or, on the contrary, strengthen destructive action the first echelon. Bcl-2 proteins (apoptosis inhibitors concern to them: A1, Bcl-2, Bcl-W, Bcl-XL, Brag-1, Mcl-1 and NR1 and Bax (apoptosis pro-motors: Bad, Bak, Bax, Bcl-XS, Bid, Bik, Bim, Hrk, Mtd). These proteins are evolutionarily conservative: the homolog of Bcl-2 is found even in sponges at which apoptosis is necessary for a morphogenesis.
splitting of antiapoptozny proteins of Bcl-family Is exposed to a proteoliz Dnkaza's inhibitor responsible for fragmentation of DNA. In normal cages apoptozny Dnkaza of CAD (caspase-activated DNase) forms an inactive complex with the CAD inhibitor designated by ICAD or. At apoptosis ICAD inhibitor with participation 3 or 7 is inactivated, and free by CAD, causing mezhnukleosomalny ruptures of a hromatin, conducts to formation of fragments of DNA with a molecular weight, the multiple molecular mass of DNA in nukleosomny particles – 180-200 couples nucleotides.
It is a little known of the PKS mechanism at plants. In comparison with natural inductors PKS chemical and physical impacts are methodically more attractive as cause synchronous apoptosis with a high exit of the dead of cages that facilitates the subsequent analysis of results. So, apoptosis can be caused in plants processing of CN-, menadiony, thermal influence.
There are two alternative points of view on genetic control of apoptosis. It agrees the first of them apoptosis represents option of implementation of genetic programs of proliferation and a differentiation of a cage. Participation in apoptosis of a serintreoninovy kinase, a factor of a transcription of NF-kB, a protooncogene with-myc and other regulators of a cellular cycle, in particular, testifies to it. According to other apoptosis has own genetic program and the mechanism of its realization.
In relation to cages of animals and the person apoptosis is in most cases connected with proteolytic activation of the cascade – families of evolutionarily conservative tsisteinovy proteases which specifically split proteins after the remains of asparaginovy acid.
The first hypothesis is especially clearly developed in works of professor Zh. Medvedev, and also L. Ordzhel from Institute of Solk in the USA. These researchers consider that aging is process of accumulation of mistakes in processes of a transcription and broadcasting and emergence of enzymes with defective functioning. Thus mechanisms of a reparation cannot will cope with escalating amount of defects.
Kaspaza-3 it is capable further to independent activation (an autocatalysis or autoprocessing), activates some other proteases of family, activates a factor of fragmentation of DNA, conducts to irreversible disintegration of DNA on nukleosomalny fragments. The cascade of the proteolytic enzymes which are carrying out apoptosis is so started.
Tsisteinovy proteases, apparently, participate also in PKS at plants. However apoptosis is possible and without participation : supersynthesis of proteins pro-motors of apoptosis of Bax and Bak induces PKS in the presence of inhibitors.