Lack of Pur-alpha alters postnatal brain development and causes megalencephaly.
Pur-alpha (Purα) plays an important role in a variety of cellular processes including transcriptional regulation, cell proliferation and oncogenic transformation. To better understand the role of Purα in the developing and mature brain, we generated Purα-deficient mice, which we were able to raise to the age of six months. Purα(-/-) mice were born with no obvious pathological condition. We obtained convincing evidence that lack of Purα prolongs the postnatal proliferation of neuronal precursor cells both in the hippocampus and in the cerebellum, however, without affecting the overall number of postmitotic neurons. Independent of these findings, we observed alterations in the expression and distribution of the dendritic protein MAP2, the translation of which has been proposed previously to be Purα-dependent. At the age of 2 weeks, Purα(-/-) mice generated a continuous tremor which persisted throughout lifetime. Finally, adult Purα(-/-) mice displayed a megalencephaly and histopathological findings including axonal swellings and hyperphosphorylation of neurofilaments. Our studies underline the importance of Purα in the proliferation of neuronal precursor cells during postnatal brain development and suggest a role for Purα in the regulation of the expression and cellular distribution of dendritic and axonal proteins. Since recent studies implicate a link between Purα and the fragile X tremor/ataxia syndrome, our Purα(-/-) mouse model will provide new opportunities for understanding the mechanisms of neurodegeneration.
Center of Neuropathology and Prion Research, Ludwig-Maximilians-Universität and German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany.
Suvi
S
Hokkanen
Heidi M
HM
Feldmann
Haiyan
H
Ding
Christian K E
CK
Jung
Lukasz
L
Bojarski
Ingrid
I
Renner-Müller
Ulrich
U
Schüller
Hans
H
Kretzschmar
Eckhard
E
Wolf
Jochen
J
Herms
D000818:Animals; D001369:Axons / Q000378:metabolism; D001921:Brain / Q000254:growth & development* / Q000473:pathology*; D001923:Brain Chemistry; D049109:Cell Proliferation; D002531:Cerebellum / Q000166:cytology / Q000254:growth & development / Q000473:pathology; D054022:Cerebrum / Q000254:growth & development / Q000473:pathology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology / Q000254:growth & development; D006984:Hypertrophy; D051379:Mice; D018345:Mice, Knockout; D008869:Microtubule-Associated Proteins / Q000032:analysis; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology*; D016900:Neurofilament Proteins / Q000378:metabolism; D010766:Phosphorylation
D004268:DNA-Binding Proteins; D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins; D016900:Neurofilament Proteins; C121485:Pura protein, mouse