Articles in 2010

Sensory deprivation such as deafness or blindness leads to specific functional and neural reorganization. A new study gives insight into why and how certain abilities change, while others remain unaltered after the loss of a sense.

Disruption of DNA methylation in the brain can impair learning and memory in rodents. In this Perspective, Day and Sweatt provide an overview of evidence that implicates this epigenetic mechanism in memory processes and discuss how past controversies can be explained in light of recent findings.

This Review discusses the current knowledge regarding regulation of epigenetic modifications and mechanisms in the nervous system in response to dynamic signals such as developmental stage, growth factors and synaptic activity.

This perspective discusses the role of epigenetic mechanisms in regulating circadian rhythms, and emphasizes that the role of peripheral machinery is key for a fuller understanding of this regulation.

This review examines evidence supporting diverse roles for epigenetic mechanisms in regulating specific aspects of adult neurogenesis and their implications.

This commentary provides a nuanced discussion on the conceptual framework to study epigenetic mechanisms that regulate brain function and plasticity. By drawing from examples in genomic imprinting, the authors highlight the challenges facing epigenetics research in the context of neuroscience.

The established conductance hierarchy of voltage-gated calcium channels, where conductance of Ca_V1 is greater than Ca_V2, which is in turn greater than Ca_V3, was determined using nonphysiological divalent ion concentrations. Weber et al. find that Ca_V2.2 conductance is greater than that of Ca_V1 and Ca_V3 and investigate implications for Ca²⁺ nanodomain signaling.

Rouaux and Arlotta show that expression of a single transcription factor, Fezf2, suffices to turn ventral forebrain progenitors committed to a striatal GABAergic fate into glutamatergic corticofugal projection neurons—which nevertheless migrate to the striatum.

Primary auditory cortex is organized tonotopically along one axis. Using laser scanning photostimulation in acute slices, the authors find that local connections along the tonotopic axis differ from those along the orthogonal, isofrequency axis.

Using optogenetic techniques, Dhawale et al. find that, although sister mitral cells (which receive input from the same olfactory glomerulus) have highly correlated average spike rate responses, their spike timing with respect to respiration differs. This suggests that sister cells carry both correlated and independent information.

Could similar changes in SOD1 underlie both familial and sporadic ALS? Here, Bosco et al. find that wild-type SOD1 from sporadic ALS tissues shows conformational changes similar to those seen in familial ALS and that aberrant wild-type SOD1 can be pathogenic, potentially as a result of the same SOD1-dependent mechanism seen in familial ALS.

Agetsuma and colleagues find that the pathway between the lateral subnucleus of the dorsal habenula (dHbL) and the interpeduncular nucleus is involved in mediating experience-dependent fear responses in zebrafish. Genetic inactivation of the dHbL biased fish towards freezing, rather than the typical flight behavior, in response to a conditioned fear stimulus.

Lomber and colleagues find that enhanced visual localization and motion detection in deaf cats is subserved by cross-modal reorganization of cortex that is typically dedicated to auditory function. Furthermore, the authors localize the individual visual functions to discrete portions of reorganized auditory cortex.

How extracellular signals, such as BDNF, regulate axonal branching is unclear. Here, Jeanneteau et al. find that MAP kinase phosphatase 1 expression is induced by BDNF signaling to deactivate JNK. This negatively regulates phosphorylation of JNK substrates that impinge on microtubule destabilization. Neurons from mkp-1 null mice were unable to produce BDNF-induced axon branches.

This study demonstrates that Fbw7, a component of ubiquitin ligase complex, regulates neural progenitor cell viability and differentiation by controlling Notch and JNK/c-Jun signaling.

Hereditary spastic paraplegia (HSP) is manifested as motor dysfunction stemming from axonal degeneration. Of the known 19 spastic paraplegia genes (SPGs), SPG3a encodes a multimeric integral membrane protein Atlastin. Here, the authors use zebrafish system to demonstrate the interplay between Atlastin and bone morphogenic protein signaling in motor axon development and stability.

Integrins connect cells to the extracellular matrix and mediate neuron-neuron or neuron-glia interactions during synapse maturation and synaptic plasticity. Here, Charrier et al. find that integrins β1 and β3 exert opposing actions via CaMKII to regulate glycine receptor lateral diffusion and gephyrin trafficking at the inhibitory synapses in spinal cord neurons.

Corticotrophin releasing factor (CRF) and its receptors are involved in the neuroendocrine and behavioral responses to stress. Here, Elliot and colleagues describe alterations in DNA methylation of the Crf gene that regulate its expression and show that these alterations correlate with resilience to social stress.

A continuum of acoustically varying speech sounds is not perceived as a continuum, but as distinct phonetic categories. Chang et al. recorded directly from human posterior superior temporal gyrus and found that this area has a similarly discontinuous coding of objectively continuous sound, matching perception and indicating higher-level processing.

Dombeck and colleagues describe a method for two-photon calcium imaging using a genetically encoded indicator in the hippocampus of awake, behaving mice. This powerful approach permits the recording of multiple hippocampal place cells' activity with subcellular resolution as the mice run on a track in a virtual reality environment.