Early postnatal ataxia and abnormal cerebellar development in mice lacking Xeroderma pigmentosum Group A and Cockayne syndrome Group B DNA repair genes.
Xeroderma pigmentosum (XP) and Cockayne syndrome (CS) are rare autosomal recessive disorders associated with a defect in the nucleotide excision repair (NER) pathway required for the removal of DNA damage induced by UV light and distorting chemical adducts. Although progressive neurological dysfunction is one of the hallmarks of CS and of some groups of XP patients, the causative mechanisms are largely unknown. Here we show that mice lacking both the XPA (XP-group A) and CSB (CS-group B) genes in contrast to the single mutants display severe growth retardation, ataxia, and motor dysfunction during early postnatal development. Their cerebella are hypoplastic and showed impaired foliation and stunted Purkinje cell dendrites. Reduced neurogenesis and increased apoptotic cell death occur in the cerebellar external granular layer. These findings suggest that XPA and CSB have additive roles in the mouse nervous system and support a crucial role for these genes in normal brain development.
Murai
M
M
Division of Protein Biosynthesis, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
Enokido
Y
Y
Inamura
N
N
Yoshino
M
M
Nakatsu
Y
Y
van der Horst
G T
GT
Hoeijmakers
J H
JH
Tanaka
K
K
Hatanaka
H
H
D000818:Animals; D017209:Apoptosis; D001259:Ataxia / Q000235:genetics*; D001522:Behavior, Animal; D002531:Cerebellum / Q000254:growth & development* / Q000473:pathology; D003057:Cockayne Syndrome / Q000235:genetics; D004265:DNA Helicases / Q000235:genetics / Q000502:physiology*; D004260:DNA Repair / Q000235:genetics*; D045643:DNA Repair Enzymes; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D000075223:Poly-ADP-Ribose Binding Proteins; D014983:Xeroderma Pigmentosum / Q000235:genetics; D051760:Xeroderma Pigmentosum Group A Protein
D004268:DNA-Binding Proteins; D000075223:Poly-ADP-Ribose Binding Proteins; D051760:Xeroderma Pigmentosum Group A Protein; C497315:Xpa protein, mouse; D004265:DNA Helicases; C513075:Ercc6 protein, mouse; D045643:DNA Repair Enzymes