BaxInactivation in Lurcher Mutants Rescues Cerebellar Granule Cells But Not Purkinje Cells or Inferior Olivary Neurons

Intrauterine growth restriction (IUGR) can lead to adverse neurodevelopmental sequelae in postnatal life. However, the effects of IUGR on the cerebellum are still to be fully elucidated. A major determinant of growth and development of the cerebellum is proliferation and subsequent migration of cerebellar granule cells. Our objective was to determine whether IUGR, induced by chronic placental insufficiency (CPI) in guinea pigs, results in abnormal cerebellar development due to deficits suggestive of impaired granule cell proliferation and/or migration. CPI was induced by unilateral ligation of the uterine artery at mid-gestation, producing growth-restricted (GR) foetuses at 52 and 60 days of gestation (dg), and neonates at 1 week postnatal age (term approx. 67 dg). Controls were from sham-operated animals. In GR foetuses compared with controls at 52 dg, the external granular layer (EGL) width and internal granular layer (IGL) area were similar. In GR foetuses compared with controls at 60 dg: (a) the EGL width was greater (p < 0.005); (b) the IGL area was smaller (p < 0.005); (c) the density of Ki67-negative (postmitotic) granule cells in the EGL was greater (p < 0.01); (d) the somal area of Purkinje cells was reduced (p < 0.005), and (e) the linear density of Bergmann glia was similar. The EGL width in GR foetuses at 60 dg was comparable to that of 52 dg control and GR foetuses. The pattern of p27-immunoreactivity in the EGL was the inverse of Ki67-immunoreactivity at both foetal ages; there was no difference between control and GR foetuses at either age in the width of p27-immunoreactivity, or in the percentage of the EGL width that it occupied. In the molecular layer of GR neonates compared with controls there was an increase in the areal density of granule cells (p < 0.05) and in the percentage of migrating to total number of granule cells (p < 0.01) at 1 week but not at 60 dg (p > 0.05). Thus, we found no specific evidence that IUGR affects granule cell proliferation, but it alters the normal program of migration to the IGL and, in addition, the development of Purkinje cells. Such alterations will likely affect the development of appropriate circuitry and have implications for cerebellar function.

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Inositol Hexakisphosphate Kinase-2 in Cerebellar Granule Cells Regulates Purkinje Cells and Motor Coordination via Protein 4.1N

Journal of Neuroscience ◽

10.1523/jneurosci.1165-18.2018 ◽

2018 ◽

Vol 38 (34) ◽

pp. 7409-7419 ◽

Cited By ~ 2

Author(s):

Latika Nagpal ◽

Chenglai Fu ◽

Solomon H. Snyder

Keyword(s):

Purkinje Cells ◽

Motor Coordination ◽

Granule Cells ◽

Cerebellar Granule Cells ◽

Inositol Hexakisphosphate ◽

Cerebellar Granule

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The 270 kDa splice variant of erythrocyte beta-spectrin (beta I sigma 2) segregates in vivo and in vitro to specific domains of cerebellar neurons

Journal of Cell Science ◽

10.1242/jcs.106.1.67 ◽

1993 ◽

Vol 106 (1) ◽

pp. 67-78 ◽

Cited By ~ 4

Author(s):

F. Malchiodi-Albedi ◽

M. Ceccarini ◽

J.C. Winkelmann ◽

J.S. Morrow ◽

T.C. Petrucci

Keyword(s):

Purkinje Cells ◽

Granule Cells ◽

Cerebellar Granule Cells ◽

Membrane Surface ◽

Granular Cells ◽

Cerebellar Neurons ◽

Cerebellar Granule ◽

Sigma 1 ◽

Alpha Spectrin ◽

Alpha Beta

Spectrin isoforms arise from four distinct genes, three of which generate multiple alternative transcripts. With no biochemical restrictions on the assembly of alpha beta heterodimers, more than 25 distinct heterodimeric spectrin species may exist. Whether (and why) this subtle but substantial diversity is realized in any single cell is unknown. To address this question, sequence-specific antibodies to alternatively spliced regions of alpha- and beta-spectrin have been prepared. Reported here is the localization in rat cerebellar neurons at light and electron microscopic levels of an antibody against a unique sequence (beta I sigma 2-A = PGQHKDGQKSTGDERPT) from the 270 kDa transcript of the red cell beta-spectrin gene (spectrin beta I sigma 2). In this version, the 3′ sequence of erythroid beta-spectrin (beta I sigma 1) is replaced with an alternative sequence that shares substantial homology with the 3′ sequence of non-erythroid beta-spectrin (beta II sigma 1). The antibody to beta I sigma 2-A stains a single protein band at 270 kDa, determined by western blotting, in both rat cerebellum and in cultured cerebellar granule cells, and does not react with beta II sigma 1 spectrin (beta-fodrin). This antibody stains the dendritic spines of Purkinje cells in the molecular layer, and is concentrated at postsynaptic densities (PSDs) adjacent to synapsin I (which is confined to the presynaptic membrane). The soma of Purkinje cells do not stain. In the granular layer, cytoplasmic organelles and the postsynaptic densities of granular cells stain strongly. Astrocytes are also stained. In all cells, plasma membrane staining is confined to postsynaptic densities (PSD). The beta I sigma 2 isoform co-immunoprecipitates with non-erythroid alpha-spectrin (alpha II sigma), even though the distribution of alpha II sigma within neurons only partially overlaps that of beta I sigma 2. No hybrid beta I sigma 2 and beta II sigma 1 (beta-fodrin) spectrin complexes appear to exist. Spectrin beta I sigma 2 is also polarized in cultured rat cerebellar granule cells, where it is abundant in cell bodies but not neurites. The overall distribution of beta I sigma 2 is as a subset of the distribution of spectrins 240/235E previously detected with a generally reactive erythrocyte alpha beta-spectrin antibody. These findings establish the highly precise segregation of a beta-spectrin isoform to distinct cytoplasmic and membrane surface domains, indicate that it is complexed (partially) with non-erythroid alpha-spectrin, and demonstrate that cytoskeletal targeting mechanisms are preserved in cultured granular cells.(ABSTRACT TRUNCATED AT 400 WORDS)

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Neurotrophin-3 induced by tri-iodothyronine in cerebellar granule cells promotes Purkinje cell differentiation

The Journal of Cell Biology ◽

10.1083/jcb.122.2.443 ◽

1993 ◽

Vol 122 (2) ◽

pp. 443-450 ◽

Cited By ~ 125

Author(s):

D Lindholm ◽

E Castrén ◽

P Tsoulfas ◽

R Kolbeck ◽

M da P Berzaghi ◽

...

Keyword(s):

Cell Differentiation ◽

Purkinje Cell ◽

Purkinje Cells ◽

Calcium Binding ◽

Granule Cells ◽

Cerebellar Granule Cells ◽

Granule Neurons ◽

Cerebellar Granule ◽

Neurotrophin 3

Thyroid hormones play an important role in brain development, but the mechanism(s) by which triiodothyronine (T3) mediates neuronal differentiation is poorly understood. Here we demonstrate that T3 regulates the neurotrophic factor, neurotrophin-3 (NT-3), in developing rat cerebellar granule cells both in cell culture and in vivo. In situ hybridization experiments showed that developing Purkinje cells do not express NT-3 mRNA but do express trkC, the putative neuronal receptor for NT-3. Addition of recombinant NT-3 to cerebellar cultures from embryonic rat brain induces hypertrophy and neurite sprouting of Purkinje cells, and upregulates the mRNA encoding the calcium-binding protein, calbindin-28 kD. The present study demonstrates a novel interaction between cerebellar granule neurons and developing Purkinje cells in which NT-3 induced by T3 in the granule cells promotes Purkinje cell differentiation.

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