| First Author | Ji Z | Year | 1997 |
| Journal | J Comp Neurol | Volume | 378 |
| Issue | 3 | Pages | 354-62 |
| PubMed ID | 9034896 | Mgi Jnum | J:38768 |
| Mgi Id | MGI:86153 | Doi | 10.1002/(sici)1096-9861(19970217)378:3<354::aid-cne4>3.0.co;2-2 |
| Citation | Ji Z, et al. (1997) Evidence of spinocerebellar mossy fiber segregation in the juvenile staggerer cerebellum. J Comp Neurol 378(3):354-62 |
| abstractText | Developmental and experimental studies of climbing fiber and messy fiber connectivity in the cerebellum have suggested that Purkinje cells are the critical organizing elements for connectivity patterns. This hypothesis is supported by evidence that spinocerebellar messy fiber projections are abnormally diffuse in P25 sg/sg mutant mice in which the differentiation of a reduced number of sg/sg Purkinje cells is blocked due to a cell autonomous defect. However, messy fiber distribution may be disrupted in sg/sg mutants not because of the Purkinje cell deficits, but because of the death of virtually all granule cells following the 4th postnatal week. To test this hypothesis, we have analyzed the distribution of wheat germ agglutinin-horseradish peroxidase (WGA-HRP)- labeled spinocerebellar messy fiber terminals in sg/sg mutants at the end of the period of granule cell genesis (postnatal day [P]12-P13) and before massive granule cell death (P16). Two percent WGA-HRP was injected into the lower thoracic/upper lumbar region of the spinal cord of eight homozygous sg/sg mutants (P12-P16) and five controls (+/sg and +/+). We have found that spinocerebellar messy fibers segregate into distinct terminal fields in the anterior cerebellar lobules of P12 to P16 sg/sg mutants, although the medial-lateral distribution of spinocerebellar messy fiber projections is different from controls. The results from this study and previous analysis of sg/sg mutants support the hypothesis that topographic cues are expressed in the early postnatal staggerer mutant, but messy fiber terminals become disorganized or retract as granule cells die in the older staggerer mutant. (C) 1997 Wiley-Liss, Inc. |
