22) DNA-PK and ATM have also similarities in some biochemical properties, e.
In our earlier study, radiation-induced phosphorylation of XRCC4 was diminished in DNA-PKcs-deficient human glioma M059J cells and also suppressed by the treatment with wortmannin, which inhibits DNA-PK activity.
Nevertheless, the scientists discovered that the DNA breaks during HIV integration surprisingly activate DNA-PK, which then performs an unusually destructive role: eliciting a signal that causes the CD4+ T cell to die.
According to the scientists, these new findings suggest that treating HIV-infected individuals with drugs that block early steps of viral replication-up to and including activation of DNA-PK and integration-not only can prevent viral replication, but also may improve CD4+ T cell survival and immune function.
According to the scientists, these new findings suggest that treating HIV-infected individuals with drugs that block early steps of viral replication -- up to and including activation of DNA-PK
and integration -- not only can prevent viral replication, but also may improve CD4+ T cell survival and immune function.
But the new treatment has been found to attack and destroy DNA-PK.
Dr Willmore added: "Our research shows that patients with lots of DNA-PK in their blood respond the worst to treatment because it is protecting the cancer from chemotherapy.
These results suggest that chrysotile-induced Ser15 phosphorylation is dependent on PIKK family such as DNA-PK
and ATM, and support the possible role of Ser15 phosphorylation in the accumulation of p53 protein.
However, the catalytic subunit of DNA-PK
can be activated by another DNA-binding protein, heat shock transcription factor 1 (Peterson et al.
, which stands for DNA-dependent protein kinase, has already been the subject of much research because it helps repair breaks in the DNA.
Although the catalytic and regulatory subunits of DNA-PK
remain to be characterized in this organism, DNA-dependent phosphorylation of histone during nucleosome assembly has been demonstrated in the oocytes (Kleinschimdt and Steinbeisser, 1991).
We performed in vitro DNA-dependent kinase assays using a specific peptide derived from p53 -- a known substrate of human DNA-PK