Limits...
Neuropilins define distinct populations of neural crest cells.

Lumb R, Wiszniak S, Kabbara S, Scherer M, Harvey N, Schwarz Q - Neural Dev (2014)

Bottom Line: Taken together, our results demonstrate that Nrp1 and Nrp2 are expressed in different populations of NCCs, and that Nrp2-expressing NCCs are strongly biased towards a sensory fate.In the trunk, Nrp2-expressing NCCs specifically give rise to sensory ganglia, whereas Nrp1-expressing NCCs likely give rise to both sensory and sympathetic ganglia.Our findings therefore suggest that neuropilins play an essential role in coordinating NCC migration with fate specification.

View Article: PubMed Central - PubMed

Affiliation: Centre for Cancer Biology, University of South Australia and SA Pathology, Frome Road, Adelaide 5000, Australia. quenten.schwarz@health.sa.gov.au.

ABSTRACT

Background: Neural crest cells (NCCs) are a transient embryonic cell type that give rise to a wide spectrum of derivatives, including neurons and glia of the sensory and autonomic nervous system, melanocytes and connective tissues in the head. Lineage-tracing and functional studies have shown that trunk NCCs migrate along two distinct paths that correlate with different developmental fates. Thus, NCCs migrating ventrally through the anterior somite form sympathetic and sensory ganglia, whereas NCCs migrating dorsolaterally form melanocytes. Although the mechanisms promoting migration along the dorsolateral path are well defined, the molecules providing positional identity to sympathetic and sensory-fated NCCs that migrate along the same ventral path are ill defined. Neuropilins (Nrp1 and Nrp2) are transmembrane glycoproteins that are essential for NCC migration. Nrp1 and Nrp2 knockout mice have disparate phenotypes, suggesting that these receptors may play a role in sorting NCCs biased towards sensory and sympathetic fates to appropriate locations.

Results: Here we have combined in situ hybridisation, immunohistochemistry and lineage-tracing analyses to demonstrate that neuropilins are expressed in a non-overlapping pattern within NCCs. Whereas Nrp1 is expressed in NCCs emigrating from hindbrain rhombomere 4 (r4) and within trunk NCCs giving rise to sympathetic and sensory ganglia, Nrp2 is preferentially expressed in NCCs emigrating from r2 and in trunk NCCs giving rise to sensory ganglia. By generating a tamoxifen-inducible lineage-tracing system, we further demonstrate that Nrp2-expressing NCCs specifically populate sensory ganglia including the trigeminal ganglia (V) in the head and the dorsal root ganglia in the trunk.

Conclusions: Taken together, our results demonstrate that Nrp1 and Nrp2 are expressed in different populations of NCCs, and that Nrp2-expressing NCCs are strongly biased towards a sensory fate. In the trunk, Nrp2-expressing NCCs specifically give rise to sensory ganglia, whereas Nrp1-expressing NCCs likely give rise to both sensory and sympathetic ganglia. Our findings therefore suggest that neuropilins play an essential role in coordinating NCC migration with fate specification.

Show MeSH

Related in: MedlinePlus

Nrp2-expressing NCCs give rise to neurons and glia of the trigeminal ganglia. (A) Whole mount X-gal staining of E11.5 Nrp2-CreERT2/Kikume X R26R embryos injected with tamoxifen (TM) at E9.5 and E10.0 (arrows). Staining was restricted to the trigeminal ganglia (V) that were derived from the r2 stream of NCCs. Notably, staining was absent from derivatives of the r4 stream of NCCs such as the facio-acoustic ganglia (VII-VIII). (B-C) Longitudinal sections through the head of Nrp2-CreERT2/Kikume X R26R embryos counterstained for X-gal and eosin confirmed that transgene expression was restricted to the trigeminal ganglia (V) and lacking in the facio-acoustic ganglia (VII-VIII). (D-G) Serial sections to that in (B) counterstained for X-gal, Tuj1, and Sox9 confirmed transgene expression within neurons and glia of the trigeminal ganglia (V) and not within the facio-acoustic ganglia (VII-VIII). (D) Bright-field (BF) images of X-gal staining overlaid with Tuj1 and Sox9. (G) BF images were colour-inverted to cyan to promote colocalisation analysis. (Gi-Gi′′′ X-gal-positive descendants of Nrp2-expressing NCCs co-expressed Tuj1 (arrow). (Gii-Gii′′′) X-gal-positive descendants of Nrp2-expressing NCCs co-expressed Sox9 (arrow). Scale bars = A, 500 μm; D, G, 100 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4233049&req=5

Fig7: Nrp2-expressing NCCs give rise to neurons and glia of the trigeminal ganglia. (A) Whole mount X-gal staining of E11.5 Nrp2-CreERT2/Kikume X R26R embryos injected with tamoxifen (TM) at E9.5 and E10.0 (arrows). Staining was restricted to the trigeminal ganglia (V) that were derived from the r2 stream of NCCs. Notably, staining was absent from derivatives of the r4 stream of NCCs such as the facio-acoustic ganglia (VII-VIII). (B-C) Longitudinal sections through the head of Nrp2-CreERT2/Kikume X R26R embryos counterstained for X-gal and eosin confirmed that transgene expression was restricted to the trigeminal ganglia (V) and lacking in the facio-acoustic ganglia (VII-VIII). (D-G) Serial sections to that in (B) counterstained for X-gal, Tuj1, and Sox9 confirmed transgene expression within neurons and glia of the trigeminal ganglia (V) and not within the facio-acoustic ganglia (VII-VIII). (D) Bright-field (BF) images of X-gal staining overlaid with Tuj1 and Sox9. (G) BF images were colour-inverted to cyan to promote colocalisation analysis. (Gi-Gi′′′ X-gal-positive descendants of Nrp2-expressing NCCs co-expressed Tuj1 (arrow). (Gii-Gii′′′) X-gal-positive descendants of Nrp2-expressing NCCs co-expressed Sox9 (arrow). Scale bars = A, 500 μm; D, G, 100 μm.

Mentions: Using this inducible lineage-tracing mouse model, we first determined the derivatives of Nrp2-expressing NCCs in the head. Tamoxifen was administered to pregnant dams when embryos were at E9.5 and E10.0, and later collected at E11.5. Consistent with Nrp2 being restricted to specific cranial NCC subpopulations, analysis of whole mount embryos revealed distinct X-gal staining in the trigeminal (V) ganglia that are derived from NCCs migrating out of r2 (n = 8, Figure 7A). By contrast, minimal staining was detected in r4 NCC derived structures such as the facio-acoustic ganglia (VII-VIII). X-gal staining also identified additional Nrp2-expressing cells in the forebrain region. Longitudinal sections counterstained with eosin confirmed the restriction of Nrp2-expressing NCCs to the trigeminal ganglia (V) (Figure 7B-C).Figure 7


Neuropilins define distinct populations of neural crest cells.

Lumb R, Wiszniak S, Kabbara S, Scherer M, Harvey N, Schwarz Q - Neural Dev (2014)

Nrp2-expressing NCCs give rise to neurons and glia of the trigeminal ganglia. (A) Whole mount X-gal staining of E11.5 Nrp2-CreERT2/Kikume X R26R embryos injected with tamoxifen (TM) at E9.5 and E10.0 (arrows). Staining was restricted to the trigeminal ganglia (V) that were derived from the r2 stream of NCCs. Notably, staining was absent from derivatives of the r4 stream of NCCs such as the facio-acoustic ganglia (VII-VIII). (B-C) Longitudinal sections through the head of Nrp2-CreERT2/Kikume X R26R embryos counterstained for X-gal and eosin confirmed that transgene expression was restricted to the trigeminal ganglia (V) and lacking in the facio-acoustic ganglia (VII-VIII). (D-G) Serial sections to that in (B) counterstained for X-gal, Tuj1, and Sox9 confirmed transgene expression within neurons and glia of the trigeminal ganglia (V) and not within the facio-acoustic ganglia (VII-VIII). (D) Bright-field (BF) images of X-gal staining overlaid with Tuj1 and Sox9. (G) BF images were colour-inverted to cyan to promote colocalisation analysis. (Gi-Gi′′′ X-gal-positive descendants of Nrp2-expressing NCCs co-expressed Tuj1 (arrow). (Gii-Gii′′′) X-gal-positive descendants of Nrp2-expressing NCCs co-expressed Sox9 (arrow). Scale bars = A, 500 μm; D, G, 100 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4233049&req=5

Fig7: Nrp2-expressing NCCs give rise to neurons and glia of the trigeminal ganglia. (A) Whole mount X-gal staining of E11.5 Nrp2-CreERT2/Kikume X R26R embryos injected with tamoxifen (TM) at E9.5 and E10.0 (arrows). Staining was restricted to the trigeminal ganglia (V) that were derived from the r2 stream of NCCs. Notably, staining was absent from derivatives of the r4 stream of NCCs such as the facio-acoustic ganglia (VII-VIII). (B-C) Longitudinal sections through the head of Nrp2-CreERT2/Kikume X R26R embryos counterstained for X-gal and eosin confirmed that transgene expression was restricted to the trigeminal ganglia (V) and lacking in the facio-acoustic ganglia (VII-VIII). (D-G) Serial sections to that in (B) counterstained for X-gal, Tuj1, and Sox9 confirmed transgene expression within neurons and glia of the trigeminal ganglia (V) and not within the facio-acoustic ganglia (VII-VIII). (D) Bright-field (BF) images of X-gal staining overlaid with Tuj1 and Sox9. (G) BF images were colour-inverted to cyan to promote colocalisation analysis. (Gi-Gi′′′ X-gal-positive descendants of Nrp2-expressing NCCs co-expressed Tuj1 (arrow). (Gii-Gii′′′) X-gal-positive descendants of Nrp2-expressing NCCs co-expressed Sox9 (arrow). Scale bars = A, 500 μm; D, G, 100 μm.
Mentions: Using this inducible lineage-tracing mouse model, we first determined the derivatives of Nrp2-expressing NCCs in the head. Tamoxifen was administered to pregnant dams when embryos were at E9.5 and E10.0, and later collected at E11.5. Consistent with Nrp2 being restricted to specific cranial NCC subpopulations, analysis of whole mount embryos revealed distinct X-gal staining in the trigeminal (V) ganglia that are derived from NCCs migrating out of r2 (n = 8, Figure 7A). By contrast, minimal staining was detected in r4 NCC derived structures such as the facio-acoustic ganglia (VII-VIII). X-gal staining also identified additional Nrp2-expressing cells in the forebrain region. Longitudinal sections counterstained with eosin confirmed the restriction of Nrp2-expressing NCCs to the trigeminal ganglia (V) (Figure 7B-C).Figure 7

Bottom Line: Taken together, our results demonstrate that Nrp1 and Nrp2 are expressed in different populations of NCCs, and that Nrp2-expressing NCCs are strongly biased towards a sensory fate.In the trunk, Nrp2-expressing NCCs specifically give rise to sensory ganglia, whereas Nrp1-expressing NCCs likely give rise to both sensory and sympathetic ganglia.Our findings therefore suggest that neuropilins play an essential role in coordinating NCC migration with fate specification.

View Article: PubMed Central - PubMed

Affiliation: Centre for Cancer Biology, University of South Australia and SA Pathology, Frome Road, Adelaide 5000, Australia. quenten.schwarz@health.sa.gov.au.

ABSTRACT

Background: Neural crest cells (NCCs) are a transient embryonic cell type that give rise to a wide spectrum of derivatives, including neurons and glia of the sensory and autonomic nervous system, melanocytes and connective tissues in the head. Lineage-tracing and functional studies have shown that trunk NCCs migrate along two distinct paths that correlate with different developmental fates. Thus, NCCs migrating ventrally through the anterior somite form sympathetic and sensory ganglia, whereas NCCs migrating dorsolaterally form melanocytes. Although the mechanisms promoting migration along the dorsolateral path are well defined, the molecules providing positional identity to sympathetic and sensory-fated NCCs that migrate along the same ventral path are ill defined. Neuropilins (Nrp1 and Nrp2) are transmembrane glycoproteins that are essential for NCC migration. Nrp1 and Nrp2 knockout mice have disparate phenotypes, suggesting that these receptors may play a role in sorting NCCs biased towards sensory and sympathetic fates to appropriate locations.

Results: Here we have combined in situ hybridisation, immunohistochemistry and lineage-tracing analyses to demonstrate that neuropilins are expressed in a non-overlapping pattern within NCCs. Whereas Nrp1 is expressed in NCCs emigrating from hindbrain rhombomere 4 (r4) and within trunk NCCs giving rise to sympathetic and sensory ganglia, Nrp2 is preferentially expressed in NCCs emigrating from r2 and in trunk NCCs giving rise to sensory ganglia. By generating a tamoxifen-inducible lineage-tracing system, we further demonstrate that Nrp2-expressing NCCs specifically populate sensory ganglia including the trigeminal ganglia (V) in the head and the dorsal root ganglia in the trunk.

Conclusions: Taken together, our results demonstrate that Nrp1 and Nrp2 are expressed in different populations of NCCs, and that Nrp2-expressing NCCs are strongly biased towards a sensory fate. In the trunk, Nrp2-expressing NCCs specifically give rise to sensory ganglia, whereas Nrp1-expressing NCCs likely give rise to both sensory and sympathetic ganglia. Our findings therefore suggest that neuropilins play an essential role in coordinating NCC migration with fate specification.

Show MeSH
Related in: MedlinePlus