Key Specifications Table
|Species Reactivity||Key Applications||Host||Format||Antibody Type|
|B, Ch, H, M, Po, R, Qu, Rb, Rp||ICC, IHC, IH(P), WB||Rb||Serum||Polyclonal Antibody|
|Presentation||Neat rabbit antiserum containing no preservative.|
|Safety Information according to GHS|
|Material Size||50 µL|
Anti-Neurofilament M (145 kDa) Antibody, CT SDS
|Reference overview||Application||Species||Pub Med ID|
|Why are enteric ganglia so small? Role of differential adhesion of enteric neurons and enteric neural crest cells.|
Rollo, BN; Zhang, D; Simkin, JE; Menheniott, TR; Newgreen, DF
F1000Research 4 113 2015
The avian enteric nervous system (ENS) consists of a vast number of unusually small ganglia compared to other peripheral ganglia. Each ENS ganglion at mid-gestation has a core of neurons and a shell of mesenchymal precursor/glia-like enteric neural crest (ENC) cells. To study ENS cell ganglionation we isolated midgut ENS cells by HNK-1 fluorescence-activated cell sorting (FACS) from E5 and E8 quail embryos, and from E9 chick embryos. We performed cell-cell aggregation assays which revealed a developmentally regulated functional increase in ENS cell adhesive function, requiring both Ca (2+) -dependent and independent adhesion. This was consistent with N-cadherin and NCAM labelling. Neurons sorted to the core of aggregates, surrounded by outer ENC cells, showing that neurons had higher adhesion than ENC cells. The outer surface of aggregates became relatively non-adhesive, correlating with low levels of NCAM and N-cadherin on this surface of the outer non-neuronal ENC cells. Aggregation assays showed that ENS cells FACS selected for NCAM-high and enriched for enteric neurons formed larger and more coherent aggregates than unsorted ENS cells. In contrast, ENS cells of the NCAM-low FACS fraction formed small, disorganised aggregates. This suggests a novel mechanism for control of ENS ganglion morphogenesis where i) differential adhesion of ENS neurons and ENC cells controls the core/shell ganglionic structure and ii) the ratio of neurons to ENC cells dictates the equilibrium ganglion size by generation of an outer non-adhesive surface.
|Glial ankyrins facilitate paranodal axoglial junction assembly.|
Chang, KJ; Zollinger, DR; Susuki, K; Sherman, DL; Makara, MA; Brophy, PJ; Cooper, EC; Bennett, V; Mohler, PJ; Rasband, MN
Nature neuroscience 17 1673-81 2014
Neuron-glia interactions establish functional membrane domains along myelinated axons. These include nodes of Ranvier, paranodal axoglial junctions and juxtaparanodes. Paranodal junctions are the largest vertebrate junctional adhesion complex, and they are essential for rapid saltatory conduction and contribute to assembly and maintenance of nodes. However, the molecular mechanisms underlying paranodal junction assembly are poorly understood. Ankyrins are cytoskeletal scaffolds traditionally associated with Na(+) channel clustering in neurons and are important for membrane domain establishment and maintenance in many cell types. Here we show that ankyrin-B, expressed by Schwann cells, and ankyrin-G, expressed by oligodendrocytes, are highly enriched at the glial side of paranodal junctions where they interact with the essential glial junctional component neurofascin 155. Conditional knockout of ankyrins in oligodendrocytes disrupts paranodal junction assembly and delays nerve conduction during early development in mice. Thus, glial ankyrins function as major scaffolds that facilitate early and efficient paranodal junction assembly in the developing CNS.
|A hierarchy of ankyrin-spectrin complexes clusters sodium channels at nodes of Ranvier.|
Ho, TS; Zollinger, DR; Chang, KJ; Xu, M; Cooper, EC; Stankewich, MC; Bennett, V; Rasband, MN
Nature neuroscience 17 1664-72 2014
The scaffolding protein ankyrin-G is required for Na(+) channel clustering at axon initial segments. It is also considered essential for Na(+) channel clustering at nodes of Ranvier to facilitate fast and efficient action potential propagation. However, notwithstanding these widely accepted roles, we show here that ankyrin-G is dispensable for nodal Na(+) channel clustering in vivo. Unexpectedly, in the absence of ankyrin-G, erythrocyte ankyrin (ankyrin-R) and its binding partner βI spectrin substitute for and rescue nodal Na(+) channel clustering. In addition, channel clustering is also rescued after loss of nodal βIV spectrin by βI spectrin and ankyrin-R. In mice lacking both ankyrin-G and ankyrin-R, Na(+) channels fail to cluster at nodes. Thus, ankyrin R-βI spectrin protein complexes function as secondary reserve Na(+) channel clustering machinery, and two independent ankyrin-spectrin protein complexes exist in myelinated axons to cluster Na(+) channels at nodes of Ranvier.
|Ezh2 is required for neural crest-derived cartilage and bone formation.|
Schwarz, D; Varum, S; Zemke, M; Schöler, A; Baggiolini, A; Draganova, K; Koseki, H; Schübeler, D; Sommer, L
Development (Cambridge, England) 141 867-77 2014
The emergence of craniofacial skeletal elements, and of the jaw in particular, was a crucial step in the evolution of higher vertebrates. Most facial bones and cartilage are generated during embryonic development by cranial neural crest cells, while an osteochondrogenic fate is suppressed in more posterior neural crest cells. Key players in this process are Hox genes, which suppress osteochondrogenesis in posterior neural crest derivatives. How this specific pattern of osteochondrogenic competence is achieved remains to be elucidated. Here we demonstrate that Hox gene expression and osteochondrogenesis are controlled by epigenetic mechanisms. Ezh2, which is a component of polycomb repressive complex 2 (PRC2), catalyzes trimethylation of lysine 27 in histone 3 (H3K27me3), thereby functioning as transcriptional repressor of target genes. Conditional inactivation of Ezh2 does not interfere with localization of neural crest cells to their target structures, neural development, cell cycle progression or cell survival. However, loss of Ezh2 results in massive derepression of Hox genes in neural crest cells that are usually devoid of Hox gene expression. Accordingly, craniofacial bone and cartilage formation is fully prevented in Ezh2 conditional knockout mice. Our data indicate that craniofacial skeleton formation in higher vertebrates is crucially dependent on epigenetic regulation that keeps in check inhibitors of an osteochondrogenic differentiation program.
|Null and hypomorph Prickle1 alleles in mice phenocopy human Robinow syndrome and disrupt signaling downstream of Wnt5a.|
Liu, C; Lin, C; Gao, C; May-Simera, H; Swaroop, A; Li, T
Biology open 3 861-70 2014
Planar cell polarity (PCP) signaling plays a critical role in tissue morphogenesis. In mammals, disruption of three of the six "core PCP" components results in polarity-dependent defects with rotated cochlear hair cell stereocilia and open neural tube. We recently demonstrated a role of Prickle1, a core PCP molecule in Drosophila, in mammalian neuronal development. To examine Prickle1 function along a broader developmental window, we generated three mutant alleles in mice. We show that the complete loss of Prickle1 leads to systemic tissue outgrowth defects, aberrant cell organization and disruption of polarity machinery. Curiously, Prickle1 mutants recapitulate the characteristic features of human Robinow syndrome and phenocopy mouse mutants with Wnt5a or Ror2 gene defects, prompting us to explore an association of Prickle1 with the Wnt pathway. We show that Prickle1 is a proteasomal target of Wnt5a signaling and that Dvl2, a target of Wnt5a signaling, is misregulated in Prickle1 mutants. Our studies implicate Prickle1 as a key component of the Wnt-signaling pathway and suggest that Prickle1 mediates some of the WNT5A-associated genetic defects in Robinow syndrome.
|Progressive disorganization of paranodal junctions and compact myelin due to loss of DCC expression by oligodendrocytes.|
Bull, SJ; Bin, JM; Beaumont, E; Boutet, A; Krimpenfort, P; Sadikot, AF; Kennedy, TE
The Journal of neuroscience : the official journal of the Society for Neuroscience 34 9768-78 2014
Paranodal axoglial junctions are critical for maintaining the segregation of axonal domains along myelinated axons; however, the proteins required to organize and maintain this structure are not fully understood. Netrin-1 and its receptor Deleted in Colorectal Cancer (DCC) are proteins enriched at paranodes that are expressed by neurons and oligodendrocytes. To identify the specific function of DCC expressed by oligodendrocytes in vivo, we selectively eliminated DCC from mature myelinating oligodendrocytes using an inducible cre regulated by the proteolipid protein promoter. We demonstrate that DCC deletion results in progressive disruption of the organization of axonal domains, myelin ultrastructure, and myelin protein composition. Conditional DCC knock-out mice develop balance and coordination deficits and exhibit decreased conduction velocity. We conclude that DCC expression by oligodendrocytes is required for the maintenance and stability of myelin in vivo, which is essential for proper signal conduction in the CNS.
|Slowly emerging glycinergic transmission enhances inhibition in the sound localization pathway of the avian auditory system.|
Fischl, MJ; Weimann, SR; Kearse, MG; Burger, RM
Journal of neurophysiology 111 565-72 2014
Localization of low-frequency acoustic stimuli is processed in dedicated neural pathways where coincidence-detecting neurons compare the arrival time of sound stimuli at the two ears, or interaural time disparity (ITD). ITDs occur in the submillisecond range, and vertebrates have evolved specialized excitatory and inhibitory circuitry to compute these differences. Glycinergic inhibition is a computationally significant and prominent component of the mammalian ITD pathway. However, evidence for glycinergic transmission is limited in birds, where GABAergic inhibition has been thought to be the dominant or exclusive inhibitory transmitter. Indeed, previous work showed that GABA antagonists completely eliminate inhibition in avian nuclei specialized for processing temporal features of sound, nucleus magnocellularis (NM) and nucleus laminaris (NL). However, more recent work shows that glycine is coexpressed with GABA in synaptic terminals apposed to neurons in both nuclei (Coleman WL, Fischl MJ, Weimann SR, Burger RM. J Neurophysiol 105: 2405-2420, 2011; Kuo SP, Bradley LA, Trussell LO. J Neurosci 29: 9625-9634, 2009). Here we show complementary evidence of functional glycine receptor (GlyR) expression in NM and NL. Additionally, we show that glycinergic input can be evoked under particular stimulus conditions. Stimulation at high but physiologically relevant rates evokes a slowly emerging glycinergic response in NM and NL that builds over the course of the stimulus. Glycinergic response magnitude was stimulus rate dependent, representing 18% and 7% of the total inhibitory current in NM and NL, respectively, at the end of the 50-pulse, 200-Hz stimulus. Finally, we show that the glycinergic component is functionally relevant, as its elimination reduced inhibition of discharges evoked by current injection into NM neurons.
|Responses of hair follicle-associated structures to loss of planar cell polarity signaling.|
Chang, H; Nathans, J
Proceedings of the National Academy of Sciences of the United States of America 110 E908-17 2013
The mammalian hair follicle unit consists of a central follicle and a series of associated structures: sebaceous glands, arrector pili muscles, Merkel cells, and sensory nerve endings. The architecture of this multicellular structure is highly polarized with respect to the body axes. Previous work has implicated Frizzled6 (Fz6)-mediated planar cell polarity (PCP) signaling in the initial specification of hair follicle orientation. Here we investigate the origin of polarity information among structures within the hair follicle unit. Merkel cell clusters appear to have direct access to Fz6-based polarity information, and they lose polarity in the absence of Fz6. By contrast, the other follicle-associated structures likely derive some or all of their polarity cues from hair follicles, and as a result, their orientations closely match that of their associated follicle. These experiments reveal the interplay between global and local sources of polarity information for coordinating the spatial arrangement of diverse multicellular structures. They also highlight the utility of mammalian skin as a system for quantitative analyses of biological polarity.
|S[+] Apomorphine is a CNS penetrating activator of the Nrf2-ARE pathway with activity in mouse and patient fibroblast models of amyotrophic lateral sclerosis.|
Mead, RJ; Higginbottom, A; Allen, SP; Kirby, J; Bennett, E; Barber, SC; Heath, PR; Coluccia, A; Patel, N; Gardner, I; Brancale, A; Grierson, AJ; Shaw, PJ
Free radical biology & medicine 61 438-52 2013
Compelling evidence indicates that oxidative stress contributes to motor neuron injury in amyotrophic lateral sclerosis (ALS), but antioxidant therapies have not yet achieved therapeutic benefit in the clinic. The nuclear erythroid 2-related-factor 2 (Nrf2) transcription factor is a key regulator of an important neuroprotective response by driving the expression of multiple cytoprotective genes via its interaction with the antioxidant response element (ARE). Dysregulation of the Nrf2-ARE system has been identified in ALS models and human disease. Taking the Nrf2-ARE pathway as an attractive therapeutic target for neuroprotection in ALS, we aimed to identify CNS penetrating, small molecule activators of Nrf2-mediated transcription in a library of 2000 drugs and natural products. Compounds were screened extensively for Nrf2 activation, and antioxidant and neuroprotective properties in vitro. S[+]-Apomorphine, a receptor-inactive enantiomer of the clinically approved dopamine-receptor agonist (R[-]-apomorphine), was identified as a nontoxic Nrf2 activating molecule. In vivo S[+]-apomorphine demonstrated CNS penetrance, Nrf2 induction, and significant attenuation of motor dysfunction in the SOD1(G93A) transgenic mouse model of ALS. S[+]-apomorphine also reduced pathological oxidative stress and improved survival following an oxidative insult in fibroblasts from ALS patients. This molecule emerges as a promising candidate for evaluation as a potential neuroprotective agent in ALS patients in the clinic.
|Axons are injured by antigen-specific CD8(+) T cells through a MHC class I- and granzyme B-dependent mechanism.|
Sauer, BM; Schmalstieg, WF; Howe, CL
Neurobiology of disease 59 194-205 2013
Axon injury is a central determinant of irreversible neurological deficit and disease progression in patients with multiple sclerosis (MS). CD8(+) lymphocytes (CTLs) within inflammatory demyelinated MS lesions correlate with acute axon injury and neurological deficits. The mechanisms of these correlations are unknown. We interrogated CTL-mediated axon injury using the transgenic OT-I antigen-specific CTL model system in conjunction with a chambered cortical neuron culture platform that permitted the isolated manipulation of axons independent of neuron cell bodies and glia. Interferon gamma upregulated, through a dose dependent mechanism, the axonal expression of functional major histocompatibility complex class I (MHC I) molecules competent to present immunologically-relevant antigens derived from endogenously expressed proteins. Antigen-specific CTLs formed cytotoxic immune synapses with and directly injured axons expressing antigen-loaded MHC I molecules. CTL-mediated axon injury was mechanistically dependent upon axonal MHC I antigen presentation, T cell receptor specificity and axoplasmic granzyme B activity. Despite extensive distal CTL-mediated axon injury, acute neuron cell body apoptosis was not observed. These findings present a novel model of immune-mediated axon injury and offer anti-axonal CTLs and granzyme B as targets for the therapeutic protection of axons and prevention of neurological deficits in MS patients.