The specific roles of the thalamus and the cortex in the generati

The specific roles of the thalamus and the cortex in the generation and propagation of slow oscillations are still a matter of debate (Chauvette et al., 2010; McCormick et al., 2003; Wu et al., 2008). Early results point to the neocortex as generator, as the thalamic slow oscillations do not survive decortication (Timofeev and Steriade, 1996). Moreover, cortical slow oscillations persist both upon thalamic lesions as well as in cortical find protocol slice preparations (Constantinople and Bruno, 2011; Sanchez-Vives and McCormick, 2000; Steriade et al., 1993c). In thalamocortical slice preparations, thalamic stimulation

can trigger cortical slow-wave-associated Up states; yet, the thalamus is not required for their generation (MacLean et al., 2005; Rigas and Castro-Alamancos, 2007). However, a recent study suggests a re-evaluation of the role of the thalamus, providing

Romidepsin evidence for a critical role of two intrinsic thalamic oscillators, which may interact with a synaptically based cortical oscillator (Crunelli and Hughes, 2010). This work challenges the view that the cortex is causally involved in the generation of slow oscillations in vivo. A way of causally probing the distinct roles of cortex and the thalamus involves the targeted manipulations of cortical and thalamic networks. Optogenetics can provide the tools necessary for a local and

specific interrogation of neuronal circuitry (Gradinaru et al., 2010; Zhang et al., 2007). The use of optogenetics provided critical insights into the cell type-specific induction of gamma oscillations and its consequences on information flow (Sohal et al., 2009). However, in order to investigate initiation and long-range propagation of slow oscillatory activity, optogenetics needs to be combined with an effective technique to record network activity with sufficient temporal resolution and spatial specificity. In the present study, we monitored the Ca2+ transients associated with slow-wave activity by using mainly optic fiber-based fluorometric Urease Ca2+ recordings (Adelsberger et al., 2005; Grienberger et al., 2012). For this purpose, we developed a fluorescence detection and stimulation system consisting of a multimode optical fiber used both for delivering the excitation light and for collecting the emitted fluorescence signals. For the detection of slow oscillation-associated Ca2+ network spikes, we devised an optical fiber-based approach, allowing for the excitation of Ca2+ indicator Oregon green 488 BAPTA-1 (OGB-1), the collection of emission light, and the stimulation of ChR2-expressing neurons (Figure 1A).

Pyramidal cells express mGluR7a in a uniquely high level in their

Pyramidal cells express mGluR7a in a uniquely high level in their terminals innervating O-LM cells, a signal that is unmistakable. Two bistratified cells (LK20p, LK27d) and one O-LM cell (LK06ah) were selected for reconstruction (see Supplemental Information). http://www.selleckchem.com/products/abt-199.html We thank K. Detzner, Sz. Biro, D. Kotzadimitriou, and Dr. J. Somogyi for advice and excellent technical support, Dr. B. Lasztoczi for help with analysis, and Dr. T. Szabadi and Sz. Biro for the reconstructions. One bistratified cell recoding was kindly provided by Dr. K. Hartwich. We thank Drs. Y. Dalezios and B. Hangya for advice on statistical analyses. We are grateful to Drs. Ray Guillery, D. Dupret, and B. Hangya for comments

on an earlier version of the manuscript. We thank L. Papp (Neuronelektrod, Budapest, Hungary) for designing and manufacturing miniature reference electrode drives. Z.B. was supported by grant SCIC03 of the Vienna Science and Technology Fund. “
“Marie T. Filbin,

Distinguished Professor of Biology at Hunter College in New York City, died on January 15, 2014 while visiting her family in Ireland. Following some early breakthrough work on the biochemistry of peripheral myelination, Marie’s most significant scientific contributions were in the JQ1 order understanding of the molecular mechanisms of the inhibition of axonal growth and the facilitation of axonal regeneration. Marie was a passionate and highly effective advocate for research PD184352 (CI-1040) in spinal cord injury and a tireless campaigner on behalf of patients with spinal cord disease, with some of whom she developed a deeply caring and life-long personal

relationship. Marie was the very antithesis of a “stuffy” scientist—she lived her life with flair and style, infectious charm, great (and occasionally irreverent) good humor, passion for her work, devotion to her friends and family, and was a remarkable mentor to her students. Marie T. Filbin: 1955–2014 Marie Therese Filbin was born in 1955 in the town of Lurgan, Northern Ireland, where her family had been in business for generations. She attended the University of Bath, where she received a PhD in Biochemistry in 1981 for work on the characterization of nicotinic acetylcholine receptors in the locust. In 1982, she moved to the University of Maryland for postdoctoral training without (she admitted) much detailed career planning but driven by a strong sense of adventure and discovery. The move to Baltimore proved fortuitous, however, when in 1984 she joined Gihan Tennekoon in the Department of Neurology at Johns Hopkins. In a seminal paper published with Dr. Tennekoon, Marie showed that that the tightly wound myelin leaflets that surround peripheral nerves are bound together by P0, the most abundant myelin protein, which functions as a hemophilic adhesion molecule (Filbin et al., 1990).

The fact that

a runner can make an immediate alteration <

The fact that

a runner can make an immediate alteration Selleck INK1197 in their footstrike pattern does not necessarily mean that this change is permanent. Adopting an FFS pattern places greater demands on the calf musculature.29 Thus, while patients were able to convert to an FFS pattern and significantly reduce their loading rates, additional training and conditioning of the lower leg and foot would be needed to maintain this pattern for longer duration runs. In addition, the increased load on the calf musculature, especially if it occurs suddenly, could put the runner at risk for muscle soreness or foot and ankle injuries resulting from overuse. This further supports the need for proper training, strengthening, and conditioning for a proper transition to an FFS pattern. Results of this study suggest that a runner who contacts the ground with less compliance,

or a higher vertical stiffness during IL, will exhibit a faster rise in VGRF, increasing Selleck HIF inhibitor the loading rate. We found strong correlations between the change in VILS and the changes in VALR and VILR. Both VALR and VILR, as well as VILS significantly decreased from shod running to instructed BF running (Table 2). This suggests that runners decreased their vertical stiffness in order to eliminate impact transients and reduce loading rates. The relationship between stiffness and loading rate is not always apparent in the literature due to the technique used to compute vertical stiffness. Most studies use a constant stiffness, which does not model the transient of the VGRF, thus ignoring the high stiffness during IL. For example, Shih et al.24 reported a significant increase in loading rates between an FFS and an RFS pattern that had an impact transient early in stance. However stiffness was similar between groups. Similarly, Divert et al.30 found no difference in vertical stiffness between the shod and BF runners despite reporting that only three of 12 BF runners demonstrated an impact peak. This is because, in both studies,

stiffness was assessed as an average value across the entire loading phase. The constant stiffness model misrepresents the actual vertical stiffness in cases where an impact transient exists. However, the method introduced by Hunter13 and employed in this study is an important tool that provides a more accurate computation of stiffness, particularly during initial loading. In the current study, we reported a significant reduction in VILS between the shod and BF conditions (mean (|shod| − |BF|) = 14.7 ± 9.8 kN/m, p < 0.00001). However, had the simple constant stiffness model been applied to all steps, ignoring the impact transient, the results would have actually indicated the opposite. We would have seen an increase in VILS from the shod to instructed BF condition (shod: 23.2 ± 3.9 kN/m, BF: 24.9 ± 4.1 kN/m; mean(|shod| − |BF|) = −1.7 ± 2.2 kN/m; p < 0.00001). This increase in VILS during the BF condition would greatly misrepresent what is actually occurring.

Indeed, crystallographic analysis has confirmed that disease muta

Indeed, crystallographic analysis has confirmed that disease mutations alter the shape of the nucleotide binding pocket, PLX-4720 cell line alter nucleotide loading, and

impair the normal reordering of the N-domain structure that permits cycling between alternative conformations ( Tang et al., 2010). As a consequence, the balance of VCP-adaptor interactions is altered, enhancing the interaction of VCP with some adaptors while diminishing interaction with others ( Fernández-Sáiz and Buchberger, 2010). The central question concerning the pathogenesis of VCP-related disease is which functions of VCP are altered by disease-causing mutations. To address this question in an unbiased way, we generated a Drosophila model that captures VCP mutation-dependent degeneration. Some aspects of this Drosophila model are reminiscent of the phenotypes observed in PTEN-induced putative kinase 1 (PINK1) and parkin mutant flies. Indeed, we demonstrate genetic interactions that place VCP downstream of the PINK1/Parkin pathway in vivo. Mechanistic studies JAK2 inhibitors clinical trials in vitro reveal that VCP is recruited

to mitochondria in a manner that requires Parkin-dependent ubiquitination of mitochondrial proteins. Moreover, VCP is essential to the regulated degradation of membrane proteins, including Mitofusins, and clearance of damaged mitochondria. Most importantly, these studies reveal that this function of VCP is impaired by pathogenic mutations. The species Drosophila melanogaster has a single, highly conserved ortholog of human VCP called dVCP. We developed a Drosophila model of VCP-related

disease by introducing disease-homologous mutations into dVCP. Expression directed to the eye of these animals resulted in mutation-dependent eye degeneration despite equal levels of transgene expression ( Ritson et al., 2010). Expression of wild-type dVCP in motor neurons with the driver OK371-GAL4 did not impact fly viability, whereas motor neuron expression of mutant dVCP resulted in substantial pupal lethality ( Figure 1A). The few adult escapers expressing mutant dVCP in motor neurons died shortly after eclosion. In 3rd-instar larval animals, a mutation-dependent locomotor phenotype was evident, as documented medroxyprogesterone in an assay of larval crawling ( Figure 1B). Evaluation of the neuromuscular junction (NMJ) in these animals revealed a striking mutation-dependent morphological phenotype that included reduced numbers of synaptic boutons, an accumulation of ghost boutons, and reduced density of active zones ( Figures 1C–1E and Figure S1, available online). Evaluation of NMJ morphology in rare surviving mutant dVCP adults also revealed morphological defects including an accumulation of synaptic footprints consistent with denervation ( Figure S2). Consistent with our observations in motor neurons, expression of dVCP in muscle with the driver MHC-GAL4 resulted in mutation-dependent muscle degeneration and a dropped wing phenotype ( Figure 1F and data not shown).

Besides, time-frequency

decompositions of transient chang

Besides, time-frequency

decompositions of transient changes in EEG signals typically show low-frequency specificity, spanning frequencies across multiple octaves. Here, by contrast, the phasic modulation of decision weighing was fully circumscribed to the delta range ( Figure S5), consistent with a genuinely rhythmic process. Finally, we re-estimated delta phase using a non-Fourier-based approach, namely, the Hilbert transform, and obtained the same phasic modulation of decision weighting. To do so, we band-pass-filtered single-trial EEG signals between 1 and 4 Hz and estimated the analytic phase of the EEG signals at each time point from 0 to 1,000 ms following element k at parietal electrodes (see Experimental Procedures). The preferred phase with respect FRAX597 order to the decision weight wk shifted linearly over time from 100 to 750 ms following element k—hence spanning more than one delta cycle and confirming that the phasic modulation of decision weighting is not due to a single transient Roxadustat chemical structure change in EEG signals ( Figure 5C). Besides, entering simultaneously previous (k−1), current (k), and next (k+1) elements as separate

interaction terms showed overlapping influences of delta phase on the weighting of successive elements from 300 to 650 ms following element k (p < 0.05), with opposite preferred phases for current versus previous/next elements ( Figure 5D). Several features of the data strongly suggest that the phasic modulation of neural encoding and decision weighting was not occurring at a fixed subharmonic of the 4 Hz stimulation rate. Nevertheless, we sought to confirm that

the time courses of neural encoding (Figure 2) and decision weighting (Figure 3) also reflected endogenous cortical dynamics, rather than being mainly driven by the stimulation frequency f0. To do so, we obtained additional EEG data from an independent group of 17 participants who performed the same categorization task at a different stimulation rate of 3 Hz (see Supplemental Information). We compared the estimated neural encoding and decision weighting time courses between these two data sets (Figures 6 and S6). At both stimulation rates, the peak latencies of neural encoding and decision weighting did not differ significantly tuclazepam (paired t test, both p > 0.5). And critically, we found no difference in peak latencies for neural encoding and decision weighting between the two stimulation rates (two-sample t test; neural encoding: 508 ± 20 ms at 4 Hz, 552 ± 22 ms at 3 Hz, t30 = 1.4, p > 0.1; decision weighting: 518 ± 12 ms at 4 Hz, 532 ± 34 ms at 3 Hz, t30 < 1, p > 0.5). Furthermore, while the neural encoding and decision weighting profiles for element k peaked around the onset of element k+2 at a stimulation rate of 4 Hz (t test against 500 ms; neural encoding: t14 < 1, p > 0.5; decision weighting: t14 = 1.4, p > 0.

In this analysis, seven participants (including six of the explor

In this analysis, seven participants (including six of the explorers identified by the primary model) were best LY2157299 ic50 fit with positive ε, and the remaining eight were fit with negative ε. Analysis of relative uncertainty in the explore subjects identified from this model yielded reliable effects in ventral RLPFC (XYZ = 30 56 −12; p < 0.05 [FWE cluster level]) and IPS (XYZ = 36 −46 56; p < 0.005 [FWE cluster level]). Participants with negative ε from this model did not yield positive or negative correlations of relative uncertainty with activation in RLPFC. Another reason ε could attain negative values is due to participants' tendencies to repeatedly

select the same option as previous trials click here (independent from their values; Lau and Glimcher, 2005 and Schönberg et al., 2007), where again this repeated option would have greater certainty. To factor out this perseveration or “sticky choice” component, we not only allowed the immediately preceding trial’s RT to influence the current trial, but also allowed multiple previous trials to

do so with exponential decay. This analysis allowed ε to be estimated as positive or negative across all trials. Here, six of the original eight explorers were best fit with positive ε, and the remaining participants had negative ε. This model with unconstrained ε and sticky choice provided a reliably better fit than the model without either sticky choice or uncertainty, even penalizing for the additional model complexity (improvement in ΔAIC = 31.0 [9.2]), or compared to a model that does include sticky choice but no uncertainty (ΔAIC = 3.3 [1.8]). Furthermore, as in the RT swing model, the fitted ε parameter value correlated with this improvement in fit (r = 0.51,

p = 0.05; and r = 0.53, p = 0.04 for the two model comparisons), suggesting that more positive uncertainty-driven exploration parameters are contributing to better fits rather than the negative ones. Analysis of the fMRI data restricted to the six subjects estimated to be explorers by this model still yielded reliable relative uncertainty effects in dorsal RLPFC Oxymatrine (XYZ = 26 52 16; p < 0.001 [FWE cluster level]) along with SPL (XYZ = −6 −60 60; p < 0.001 [FWE cluster level]; Table S2). Participants estimated to have a negative ε again did not show positive or negative correlations of relative uncertainty with activation in RLPFC. Finally, we constructed a model that fit categorical rather than continuous RT distributions. As already noted, a feature of the primary model is that it predicts continuous RT distributions consistent with the continuous nature of RT in this task. However, reward statistics are tracked based on two modes of responding, fast or slow.

As previously reported (Adolfsen et al , 2004), Syt4 is localized

As previously reported (Adolfsen et al., 2004), Syt4 is localized both in pre- and postsynaptic compartments of wild-type NMJs, as determined by double labeling with anti-HRP antibodies, which is used as a neuronal membrane marker to determine the boundary between presynaptic boutons and postsynaptic selleck kinase inhibitor muscles (Figure 1H). The Syt4 signal was specific, as it was virtually eliminated in syt4 null mutants ( Figure 1I).

Notably, expressing a Syt4 transgene exclusively in the neurons of syt4 null mutants rescued both the presynaptic and postsynaptic localization of Syt4 ( Figure 1J). This observation raises the possibility that presynaptic Syt4 might be transferred to the postsynaptic region and that postsynaptic Syt4 might at least be partly derived from presynaptic boutons. Consistent with this, expressing a C-terminally Myc-tagged Syt4 (Syt4-Myc) transgene in wild-type motor neurons using the OK6-Gal4 driver mimicked the endogenous localization of Syt4 in both presynaptic boutons and the postsynaptic muscle region ( Figure 1K). The same postsynaptic localization

of Syt4 was observed when expressing the transgene using either the neuronal Gal4 drivers elav-Gal4 or C380-Gal4 ( Figures S1B and S1C). Like the wild-type, untagged transgene, presynaptically expressed Syt4-Myc completely rescued the syt4 mutant phenotype upon spaced stimulation ( Figure 1N), suggesting that the tagged transgene is functional. These observations suggest that endogenous Syt4 might be transferred from synaptic boutons to muscles. This was tested by downregulating endogenous presynaptic Syt4 by expressing Syt4-RNAi in neurons. In Gemcitabine price agreement with the above model, downregulating Syt4 in motorneurons resulted in near elimination of the Syt4 signal, not only from presynaptic boutons but also from the postsynaptic muscle region (Figures 1L and 1O). Thus, the transfer of Syt4-Myc from neurons to muscles is not just the result of overexpressing the transgene in neurons but is probably

an endogenous process. Further, although Syt4-RNAi was highly efficient at decreasing Terminal deoxynucleotidyl transferase the Syt4 signal from motorneurons and muscles when expressed in motorneurons, expressing Syt4-RNAi in muscles using the strong C57-Gal4 driver did not decrease Syt4 levels in either the pre- or postsynaptic compartment (Figures 1M and 1O). These results support the idea that at least an important fraction of, if not all, postsynaptic Syt4 is derived from presynaptic neurons. We also determined whether neurons and/or muscles contained syt4 transcripts. RT-PCR using equal amounts of total RNA derived from either the nervous system or body wall muscles revealed the presence of a strong syt4 band in the nervous system ( Figure 1P). However, virtually no syt4 transcript was observed in the muscles of wild-type controls or larvae expressing Syt4-RNAi in muscles ( Figure 1P).

Prominent glutamate input to the NAc comes from the ventral hippo

Prominent glutamate input to the NAc comes from the ventral hippocampus (vHipp), basolateral amygdala, and prefrontal cortex (Friedman et al., 2002; Phillipson and Griffiths, 1985). Pathway-specific activation of these fibers has been demonstrated to elicit distinct physiological and behavioral responses (Goto and Grace, 2008; Sesack and Grace, 2010). For example, vHipp input is particularly capable of stably depolarizing NAc neurons, allowing prefrontal

cortex input to generate spike firing in these cells (O’Donnell and Grace, 1995). Basolateral amygdala input, unlike prefrontal cortex input, readily supports optogenetic self-stimulation (Stuber et al., 2011). To elucidate the mechanistic underpinnings of these types of pathway-specific effects, we examined the innervation patterns and synaptic properties of vHipp, basolateral amygdala, selleck inhibitor and prefrontal cortex input to the NAc. In addition, we assayed each pathway for cocaine-induced synaptic plasticity and subjected each one to optogenetic manipulations in vivo. To examine the innervation patterns of excitatory input to the NAc, we targeted enhanced yellow fluorescent protein (EYFP) expression to projection neurons in the vHipp, basolateral amygdala, and prefrontal cortex (Figure 1A; additional images are shown in Figure S1 available

online). When EYFP expression was measured in the NAc in images captured with identical settings, the brightest fluorescent signal was observed in vHipp fibers located in the medial NAc shell (Figure 1B). In the NAc core and lateral shell, the fluorescence VX770 coming from vHipp axons was relatively modest. In contrast, EYFP expression in the amygdala and prefrontal

cortex input, while not as pronounced in the Rolziracetam medial shell, was more apparent throughout other subregions of the ventral striatum. The innervation patterns of these two pathways were considerably uneven, yet not as localized to any specific subregion as the vHipp fibers were to the medial shell (Figures 1 and S1). To substantiate the indication that vHipp fibers predominate in the medial NAc shell, we injected the retrograde tracer Fluoro-Gold into this region (Figure 2A). This approach enabled the identification of NAc shell-projecting neurons throughout the brain (Brog et al., 1993). We identified large populations of retrogradely labeled cells in several regions, including the hippocampus (ventral subiculum and entorhinal cortex), basolateral amygdala, and prefrontal cortex (Figure 2B). Using slices from each region that contained dense populations of NAc-projecting cells, we counted more medial NAc shell-projecting neurons in the vHipp than in either the basolateral amygdala or prefrontal cortex (Figure 2C). These manual cell counts highly correlated with the anti-Fluoro-Gold fluorescent signal in each slice (Figure S2; R2 = 0.86; p < 0.

17 Considering the consequences of upper extremity injuries in ba

17 Considering the consequences of upper extremity injuries in baseball players and the fact that more and more young competitive pitchers are sustaining severe injuries, the need for research on injury prevention is greater than ever.9 Potential risk factors for upper extremity injuries Selleckchem Hydroxychloroquine in baseball players can be categorized into unsafe participation practice,1, 6, 7, 10 and 19 suboptimal physical characteristics,20, 21, 22, 23, 24 and 25 and improper pitching techniques.26, 27, 28, 29,

30, 31, 32 and 33 These studies allude to three potential approaches to preventing pitching-related upper extremity injures: 1) regulation of unsafe participation factors, 2) exercise intervention to modify suboptimal physical characteristics, and 3) instructional intervention to correct

improper pitching techniques. Participation factors that have been linked to injuries include the number of BMS-777607 supplier pitches performed in a single outing and over a course of season.1, 6, 7, 10 and 19 Based on these findings, Little League™ Baseball mandates pitch count limits to participating pitchers, and USA Baseball Medical Safety Board recommends age-specific pitch counts and rest periods to protect pitchers from overuse injuries. Physical characteristics that have been linked to upper extremity injuries in baseball players include shoulder and trunk range of motion,20, 22, 24, 34, 35 and 36 shoulder strength,37 humeral retrotorsion,38, 39 and 40 and scapular kinematics.25 It has been demonstrated from in a number of studies that most of these physical characteristics could be improved with strengthening and stretching exercises.35, 41, 42, 43, 44, 45, 46 and 47 Although there are few studies that demonstrates the effects of these exercises on injury risk reduction,43

more and more sports medicine clinicians are implementing exercise programs in hopes to prevent injuries in overhead athletes. Compared to a large number of studies that investigate participation factors and physical characteristics that are linked to injuries, there are a limited number of studies examining pitching techniques that are associated with injuries. Furthermore, no studies to date have examined the effects of pitching technique instruction on joint loading or reports of injury. Better understanding of pitching techniques that place undue stress on the shoulder and elbow joints, and implementation of an instructional program on proper pitching technique may help prevent pitching-related upper extremity injuries that occur due to poor technique. Therefore, the purpose of this review is to explore the utility of pitching technique instruction on prevention of pitching-related upper extremity injuries.

, 2011 and Jossin and Cooper, 2011), most likely by sequestering

, 2011 and Jossin and Cooper, 2011), most likely by sequestering cytoplasmic binding partners MK-8776 cell line of endogenous cadherins. Deletion of the binding site for p120ctn within DN-Cdh (Figure 6B) released the dominant-negative effect (Figures 6E and 6F), likely because p120ctn was no longer sequestered, indicating that p120ctn binding to Cdh2 is important for glia-independent somal translocation. The nectin/afadin complex does not bind p120ctn directly, but does so via the small guanosine triphosphatase (GTPase) Rap1, which binds to both afadin and p120ctn (Figure 6A) (Hoshino et al., 2005 and Sato et al., 2006). We hypothesized

that Rap1 might be the crucial link between nectin3 and afadin and Cdh2 and p120ctn pairs. Several lines of evidence support this model. First, Rap1 is required for glia-independent somal translocation, and overexpression

of Cdh2 can rescue the migration defect caused by Rap1 loss of function, demonstrating that Cdh2 acts downstream of Rap1 in this process (Franco et al., 2011). In addition, we now show that a constitutively active form of Rap1 rescued the migration defect caused by nectin3 knockdown (Figures 6C and 6D). Finally, an afadin construct lacking the Rap1 binding site (Figure 6B) acted as a dominant negative and disrupted radial migration Cobimetinib mouse (Figures 6G and 6H). Taken together, our data suggest that nectin3 in migrating neurons recruits an afadin/Rap1 complex that regulates Cdh2 function via p120ctn, thereby promoting leading-process attachment in the MZ and glia-independent somal translocation. At adherens

junctions, cadherins are recruited between neighboring cells through nectin and afadin to form stable adhesions. We therefore reasoned that CR cells might also express Cdh2 that acts in concert with nectin1 to mediate interactions with neurons. Indeed, Cdh2 was expressed in CR cells (Figures 7A and 7B). For functional tests, we electroporated the cortical hem at E11.5 with Dcx-iGFP or Dcx-DN-Cdh-iGFP GPX6 then electroporated the neocortical VZ of the same embryos at E13.5 with Dcx-mCherry to label migrating neurons. By E17.5, GFP+ CR cells had migrated into the neocortical MZ (Figure 7C), while mCherry+ radially migrating neurons populated the emerging CP (Figure 7D). Expression of DN-Cdh did not inhibit the migration of CR cells within the MZ (Figure 7C), but the positions of radially migrating neurons were significantly altered (Figures 7D and 7E). Neurons in controls migrated into the upper CP, whereas large numbers of neurons remained in the lower CP following expression of DN-Cdh in CR cells (Figures 7D and 7E). In addition, neurons in controls had leading processes that branched extensively in the MZ, but branch density was decreased following expression of DN-Cdh in CR cells (Figures 7F and 7G).