Caspase-9, a mitochondria-mediated initiation caspase, is directly activated by Apaf-1 and cytochrome c and triggers activation of execution caspases 3, 6, and 7, leading to DNA fragmentation and cell death (Li et al, 1997).
These clusters, along with those that represent biochemical control mechanisms for signaling and gene expression at the protein level, such as kinases (90 clusters) and phosphate-transfer activities (154 clusters), may represent critical elements in the activation and execution of the cellular recovery processes necessary for the mechanism of desiccation tolerance exhibited by Tortula ruralis.
The mitochondrial response includes the release of cytochrome c into the cytosol where it binds to Apaf-1, allowing the recruitment of caspase-9 and the formation of an apoptosome complex, resulting in caspase-3 activation and execution of cell death (Green and Reed 1998).
In general, the caspases are crucial for the activation and execution of apoptosis.
In studies of the DNA damage response, most attention has been focused on the activation and execution of that response.
Several genes involved in the activation or execution of apoptosis recently have been identified as E2F-1 targenesenesuchuch as p14/p19ARF and p73 [ 6- 10].
Of all the proteins involved in the activation and execution of apoptosis, the caspase 3 stands out as being crucial for this process [ 28].
This results in caspase activation, the execution phase of ER stress-induced apoptosis, and finally in the ordered and sequential dismantling of the cell.
Although their performance remained intact, there was evidence that the high-risk subjects in our study deviated from the low-risk subjects in the patterns of brain activation accompanying execution of the Tower of London task.
Our results demonstrate that overexpression of NFR1-mOrange, NFR5-mOrange, or SYMRK results in the activation and execution of the nodule organogenesis pathway in the absence of external symbiotic stimulation.
