A DNA-PKcs mutation in a radiosensitive T-B- SCID patient inhibits Artemis activation and nonhomologous end-joining
2009-01-05
Article
| Related Files |
|---|
|
Redirect to publisher's version
(publisher's version.url.txt, 34 bytes) |
Radiosensitive T-B- severe combined immunodeficiency (RS-SCID) is caused by defects in the nonhomologous end-joining (NHEJ) DNA repair pathway, which results in failure of functional V(D)J recombination. Here we have identified the first human RS-SCID patient to our knowledge with a DNA-PKcs missense mutation (L3062R). The causative mutation did not affect the kinase activity or DNA end-binding capacity of DNA-PKcs itself; rather, the presence of long P-nucleotide stretches in the immunoglobulin coding joints indicated that it caused insufficient Artemis activation, something that is dependent on Artemis interaction with autophosphorylated DNA-PKcs. Moreover, overall end-joining activity was hampered, suggesting that Artemis-independent DNA-PKcs functions were also inhibited. This study demonstrates that the presence of DNA-PKcs kinase activity is not sufficient to rule out a defect in this gene during diagnosis and treatment of RS-SCID patients. Further, the data suggest that residual DNA-PKcs activity is indispensable in humans.
- article
- cytology
- female
- human
- male
- metabolism
- priority journal
- controlled study
- genetics
- genotype
- enzyme activity
- human cell
- nonhuman
- animal
- child
- gene
- human tissue
- preschool child
- nucleotide
- DNA repair
- infant
- physiology
- nucleotide sequence
- animal cell
- molecular genetics
- amino acid sequence
- missense mutation
- gene function
- DNA binding
- case report
- cell line
- pedigree
- immunoglobulin
- radiation dose
- gene activation
- fibroblast
- nuclear protein
- DCLRE1C protein
- DNA dependent protein kinase
- autophosphorylation
- polydeoxyribonucleotide synthase
- genetic recombination
- PRKDC protein
- artemis gene
- phosphotransferase
- polydeoxyribonucleotide synthase (atp)
- radiation exposure
- sequence alignment
- severe combined immunodeficiency