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Remodeling of monoplanar Purkinje cell dendrites during cerebellar circuit formation.

Kaneko M, Yamaguchi K, Eiraku M, Sato M, Takata N, Kiyohara Y, Mishina M, Hirase H, Hashikawa T, Kengaku M - PLoS ONE (2011)

Bottom Line: Dendrites then became confined to a single plane in the fourth postnatal week.The dendrite remodeling was also impaired by pharmacological disruption of normal afferent activity during the second or third postnatal week.Our results suggest that the monoplanar arborization of Purkinje cells is coupled with functional development of the cerebellar circuitry.

View Article: PubMed Central - PubMed

Affiliation: Laboratory for Neural Cell Polarity, RIKEN Brain Science Institute, Wako, Saitama, Japan.

ABSTRACT
Dendrite arborization patterns are critical determinants of neuronal connectivity and integration. Planar and highly branched dendrites of the cerebellar Purkinje cell receive specific topographical projections from two major afferent pathways; a single climbing fiber axon from the inferior olive that extend along Purkinje dendrites, and parallel fiber axons of granule cells that contact vertically to the plane of dendrites. It has been believed that murine Purkinje cell dendrites extend in a single parasagittal plane in the molecular layer after the cell polarity is determined during the early postnatal development. By three-dimensional confocal analysis of growing Purkinje cells, we observed that mouse Purkinje cells underwent dynamic dendritic remodeling during circuit maturation in the third postnatal week. After dendrites were polarized and flattened in the early second postnatal week, dendritic arbors gradually expanded in multiple sagittal planes in the molecular layer by intensive growth and branching by the third postnatal week. Dendrites then became confined to a single plane in the fourth postnatal week. Multiplanar Purkinje cells in the third week were often associated by ectopic climbing fibers innervating nearby Purkinje cells in distinct sagittal planes. The mature monoplanar arborization was disrupted in mutant mice with abnormal Purkinje cell connectivity and motor discoordination. The dendrite remodeling was also impaired by pharmacological disruption of normal afferent activity during the second or third postnatal week. Our results suggest that the monoplanar arborization of Purkinje cells is coupled with functional development of the cerebellar circuitry.

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Related in: MedlinePlus

Multiple CF associations to multiplanar dendrites of Purkinje cells.A: Triple fluorescence for AAV-GFP-infected Purkinje cells (pseudocolored in blue), BDA-labeled CFs (magenta) and vesicular glutamate transporter VGluT2 (green). A CF targets the soma of a Purkinje cell and ramifies into several tendril fibers that run along thick stem dendrites (low magnification views on left). The varicose swellings along the CF overlap with VGluT2-positive puncta indicating CF terminals (high magnification views on right). B: Confocal (left) and graphic (right) images of CFs and a multiplanar Purkinje cell at P18. Cell-1 and Cell-2 are associated by at least 2 and 3 CFs, respectively. The main ascending fibers are indicated by arrowheads in confocal images and by yellow in graphic images. The minor CFs apposing distal dendrites (asterisks in confocal images; light and dark pink in graphic images) innervate the soma of nearby Purkinje cells (circles in confocal images). Dendrites in minor planes are pseudocolored in blue and green in graphic images. Coronal views of graphic images on right indicate that both dendrites and CFs extend in multiple sagittal planes. C: A multiplanar Purkinje cell associated with multiple CFs. This Purkinje cell extends dendrites in three distinct sagittal planes (arrows in the coronal view) and receives inputs from at least three different CFs (asterisks, filled and blank arrowheads in the sagittal view). The boxed region in the left panel is enlarged in right panels. In addition to the ascending CF in the proximal part of the dendrite (asterisks), a CF from a different origin is closely apposed to the distal part of the dendrite (arrowheads). Triple staining suggests that both the main and minor CFs form VGluT2-positive synapses on the Purkinje dendrite. Scale bars: 20 µm in B and left panels in A, C; 10 µm in right panels in A, C.
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pone-0020108-g003: Multiple CF associations to multiplanar dendrites of Purkinje cells.A: Triple fluorescence for AAV-GFP-infected Purkinje cells (pseudocolored in blue), BDA-labeled CFs (magenta) and vesicular glutamate transporter VGluT2 (green). A CF targets the soma of a Purkinje cell and ramifies into several tendril fibers that run along thick stem dendrites (low magnification views on left). The varicose swellings along the CF overlap with VGluT2-positive puncta indicating CF terminals (high magnification views on right). B: Confocal (left) and graphic (right) images of CFs and a multiplanar Purkinje cell at P18. Cell-1 and Cell-2 are associated by at least 2 and 3 CFs, respectively. The main ascending fibers are indicated by arrowheads in confocal images and by yellow in graphic images. The minor CFs apposing distal dendrites (asterisks in confocal images; light and dark pink in graphic images) innervate the soma of nearby Purkinje cells (circles in confocal images). Dendrites in minor planes are pseudocolored in blue and green in graphic images. Coronal views of graphic images on right indicate that both dendrites and CFs extend in multiple sagittal planes. C: A multiplanar Purkinje cell associated with multiple CFs. This Purkinje cell extends dendrites in three distinct sagittal planes (arrows in the coronal view) and receives inputs from at least three different CFs (asterisks, filled and blank arrowheads in the sagittal view). The boxed region in the left panel is enlarged in right panels. In addition to the ascending CF in the proximal part of the dendrite (asterisks), a CF from a different origin is closely apposed to the distal part of the dendrite (arrowheads). Triple staining suggests that both the main and minor CFs form VGluT2-positive synapses on the Purkinje dendrite. Scale bars: 20 µm in B and left panels in A, C; 10 µm in right panels in A, C.

Mentions: BDA tracer was injected into the inferior olive of the AAV-injected mice at P14, and labeled axons innervating GFP-infected Purkinje cells were assayed at P18 or P25. Some CFs were found to associate with the soma or the proximal end of the primary stem dendrite of a GFP-labeled Purkinje cell (Figure 3A). Consistent with previous observations, the ascending CFs ramified into a few branches that twisted around thick Purkinje dendrites. The tendril fibers formed numerous varicosities that overlapped with punctate expression of VGluT2, a vesicular glutamate transporter specific to CF terminals in the molecular layer [36], [37]. Notably, the multiplanar Purkinje cells were often approached by multiple distinct CFs besides the major ascending fiber (Figure 3B). The minor CFs often appeared to appose to the soma of a nearby unlabeled Purkinje cell: they entered the molecular layer without contacting with the cell body of the labeled Purkinje cell and directly approached to its distal dendrites near the border of the CF innervation territory. In all cases examined, VGLuT2+ terminals made by minor CFs were on distal branchlets and isolated from those of the main CF on proximal shafts (Figure 3C). In a coronal view, the multiple CFs apposing to a Purkinje cell ran roughly in parallel along distinct sagittal planes. The dendrite tree in the main sagittal plane was mainly associated with the primary ascending CF, while those in minor sagittal planes were approached by both the primary CF and the terminals of other CFs (Figure S4A, B). The terminals of these minor CFs were apposed to the distal branches in minor planes and formed a few VGluT2-positive varicose swellings, suggesting that they may form presynaptic terminals on the distal dendrites (Figure 3C). Since not all CFs were labeled by dye injection, we could not examine whether multiplanar Purkinje cells were always associated with multiple CFs. However, even in the multiplanar cells that were apparently associated with a single tracer-labeled ascending CF, the arbors in minor sagittal planes were often apposed to VGluT2-positive puncta that were separate from the tracer-labeled ascending CF (Figure S4C). We also compared morphological CF association to multiplanar and monoplanar Purkinje cells. Almost all multiplanar Purkinje cells appeared to appose to multiple CFs, while a large majority of monoplanar Purkinje cells were associated with a single CF at P25 (Figure S5; multiple CF associations, 16 out of 19 multiplanar cells analyzed vs. 4 out of 16 monoplanar cells analyzed). The difference in apparent CF association between multiplanar and monoplanar cells at P25 as revealed by tracer labeling was statistically significant (p<0.001; Fisher's exact test). In contrast, Purkinje cells at P18 tend to be apposed to multiple CFs at distal dendrites regardless of their configurations (17 out of 22 multiplanar cells vs. 7 out of 12 monoplanar cells; p>0.1, Fisher's exact test).


Remodeling of monoplanar Purkinje cell dendrites during cerebellar circuit formation.

Kaneko M, Yamaguchi K, Eiraku M, Sato M, Takata N, Kiyohara Y, Mishina M, Hirase H, Hashikawa T, Kengaku M - PLoS ONE (2011)

Multiple CF associations to multiplanar dendrites of Purkinje cells.A: Triple fluorescence for AAV-GFP-infected Purkinje cells (pseudocolored in blue), BDA-labeled CFs (magenta) and vesicular glutamate transporter VGluT2 (green). A CF targets the soma of a Purkinje cell and ramifies into several tendril fibers that run along thick stem dendrites (low magnification views on left). The varicose swellings along the CF overlap with VGluT2-positive puncta indicating CF terminals (high magnification views on right). B: Confocal (left) and graphic (right) images of CFs and a multiplanar Purkinje cell at P18. Cell-1 and Cell-2 are associated by at least 2 and 3 CFs, respectively. The main ascending fibers are indicated by arrowheads in confocal images and by yellow in graphic images. The minor CFs apposing distal dendrites (asterisks in confocal images; light and dark pink in graphic images) innervate the soma of nearby Purkinje cells (circles in confocal images). Dendrites in minor planes are pseudocolored in blue and green in graphic images. Coronal views of graphic images on right indicate that both dendrites and CFs extend in multiple sagittal planes. C: A multiplanar Purkinje cell associated with multiple CFs. This Purkinje cell extends dendrites in three distinct sagittal planes (arrows in the coronal view) and receives inputs from at least three different CFs (asterisks, filled and blank arrowheads in the sagittal view). The boxed region in the left panel is enlarged in right panels. In addition to the ascending CF in the proximal part of the dendrite (asterisks), a CF from a different origin is closely apposed to the distal part of the dendrite (arrowheads). Triple staining suggests that both the main and minor CFs form VGluT2-positive synapses on the Purkinje dendrite. Scale bars: 20 µm in B and left panels in A, C; 10 µm in right panels in A, C.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3105010&req=5

pone-0020108-g003: Multiple CF associations to multiplanar dendrites of Purkinje cells.A: Triple fluorescence for AAV-GFP-infected Purkinje cells (pseudocolored in blue), BDA-labeled CFs (magenta) and vesicular glutamate transporter VGluT2 (green). A CF targets the soma of a Purkinje cell and ramifies into several tendril fibers that run along thick stem dendrites (low magnification views on left). The varicose swellings along the CF overlap with VGluT2-positive puncta indicating CF terminals (high magnification views on right). B: Confocal (left) and graphic (right) images of CFs and a multiplanar Purkinje cell at P18. Cell-1 and Cell-2 are associated by at least 2 and 3 CFs, respectively. The main ascending fibers are indicated by arrowheads in confocal images and by yellow in graphic images. The minor CFs apposing distal dendrites (asterisks in confocal images; light and dark pink in graphic images) innervate the soma of nearby Purkinje cells (circles in confocal images). Dendrites in minor planes are pseudocolored in blue and green in graphic images. Coronal views of graphic images on right indicate that both dendrites and CFs extend in multiple sagittal planes. C: A multiplanar Purkinje cell associated with multiple CFs. This Purkinje cell extends dendrites in three distinct sagittal planes (arrows in the coronal view) and receives inputs from at least three different CFs (asterisks, filled and blank arrowheads in the sagittal view). The boxed region in the left panel is enlarged in right panels. In addition to the ascending CF in the proximal part of the dendrite (asterisks), a CF from a different origin is closely apposed to the distal part of the dendrite (arrowheads). Triple staining suggests that both the main and minor CFs form VGluT2-positive synapses on the Purkinje dendrite. Scale bars: 20 µm in B and left panels in A, C; 10 µm in right panels in A, C.
Mentions: BDA tracer was injected into the inferior olive of the AAV-injected mice at P14, and labeled axons innervating GFP-infected Purkinje cells were assayed at P18 or P25. Some CFs were found to associate with the soma or the proximal end of the primary stem dendrite of a GFP-labeled Purkinje cell (Figure 3A). Consistent with previous observations, the ascending CFs ramified into a few branches that twisted around thick Purkinje dendrites. The tendril fibers formed numerous varicosities that overlapped with punctate expression of VGluT2, a vesicular glutamate transporter specific to CF terminals in the molecular layer [36], [37]. Notably, the multiplanar Purkinje cells were often approached by multiple distinct CFs besides the major ascending fiber (Figure 3B). The minor CFs often appeared to appose to the soma of a nearby unlabeled Purkinje cell: they entered the molecular layer without contacting with the cell body of the labeled Purkinje cell and directly approached to its distal dendrites near the border of the CF innervation territory. In all cases examined, VGLuT2+ terminals made by minor CFs were on distal branchlets and isolated from those of the main CF on proximal shafts (Figure 3C). In a coronal view, the multiple CFs apposing to a Purkinje cell ran roughly in parallel along distinct sagittal planes. The dendrite tree in the main sagittal plane was mainly associated with the primary ascending CF, while those in minor sagittal planes were approached by both the primary CF and the terminals of other CFs (Figure S4A, B). The terminals of these minor CFs were apposed to the distal branches in minor planes and formed a few VGluT2-positive varicose swellings, suggesting that they may form presynaptic terminals on the distal dendrites (Figure 3C). Since not all CFs were labeled by dye injection, we could not examine whether multiplanar Purkinje cells were always associated with multiple CFs. However, even in the multiplanar cells that were apparently associated with a single tracer-labeled ascending CF, the arbors in minor sagittal planes were often apposed to VGluT2-positive puncta that were separate from the tracer-labeled ascending CF (Figure S4C). We also compared morphological CF association to multiplanar and monoplanar Purkinje cells. Almost all multiplanar Purkinje cells appeared to appose to multiple CFs, while a large majority of monoplanar Purkinje cells were associated with a single CF at P25 (Figure S5; multiple CF associations, 16 out of 19 multiplanar cells analyzed vs. 4 out of 16 monoplanar cells analyzed). The difference in apparent CF association between multiplanar and monoplanar cells at P25 as revealed by tracer labeling was statistically significant (p<0.001; Fisher's exact test). In contrast, Purkinje cells at P18 tend to be apposed to multiple CFs at distal dendrites regardless of their configurations (17 out of 22 multiplanar cells vs. 7 out of 12 monoplanar cells; p>0.1, Fisher's exact test).

Bottom Line: Dendrites then became confined to a single plane in the fourth postnatal week.The dendrite remodeling was also impaired by pharmacological disruption of normal afferent activity during the second or third postnatal week.Our results suggest that the monoplanar arborization of Purkinje cells is coupled with functional development of the cerebellar circuitry.

View Article: PubMed Central - PubMed

Affiliation: Laboratory for Neural Cell Polarity, RIKEN Brain Science Institute, Wako, Saitama, Japan.

ABSTRACT
Dendrite arborization patterns are critical determinants of neuronal connectivity and integration. Planar and highly branched dendrites of the cerebellar Purkinje cell receive specific topographical projections from two major afferent pathways; a single climbing fiber axon from the inferior olive that extend along Purkinje dendrites, and parallel fiber axons of granule cells that contact vertically to the plane of dendrites. It has been believed that murine Purkinje cell dendrites extend in a single parasagittal plane in the molecular layer after the cell polarity is determined during the early postnatal development. By three-dimensional confocal analysis of growing Purkinje cells, we observed that mouse Purkinje cells underwent dynamic dendritic remodeling during circuit maturation in the third postnatal week. After dendrites were polarized and flattened in the early second postnatal week, dendritic arbors gradually expanded in multiple sagittal planes in the molecular layer by intensive growth and branching by the third postnatal week. Dendrites then became confined to a single plane in the fourth postnatal week. Multiplanar Purkinje cells in the third week were often associated by ectopic climbing fibers innervating nearby Purkinje cells in distinct sagittal planes. The mature monoplanar arborization was disrupted in mutant mice with abnormal Purkinje cell connectivity and motor discoordination. The dendrite remodeling was also impaired by pharmacological disruption of normal afferent activity during the second or third postnatal week. Our results suggest that the monoplanar arborization of Purkinje cells is coupled with functional development of the cerebellar circuitry.

Show MeSH
Related in: MedlinePlus