Axon trapping: constructing the visual system one layer at a time

Zhang et?al. (2012) and Rozas et?al. (2012) in this issue of Neuron find that cysteine string protein α, a protein involved in neurodegeneration, regulates vesicle endocytosis via interaction with dynamin 1, which may participate in regulating synaptic transmission and possibly in maintaining synapses.     

Superimposed hemifields in primary visual cortex of achiasmic individuals

In the rare condition of achiasma, the visual cortex in each hemisphere receives information from both halves of the visual field. How is this "doubling" of information accommodated in V1? In this issue of Neuron, Hoffmann et?al. (2012) investigate the cortical consequences of this anomaly.     

Finally, Polyubiquitinated PCNA Gets Recognized

Studies from Ciccia et?al. (2012) and Yuan et?al. (2012) in this issue of Molecular Cell, together with Weston et?al. (2012), reveal that the translocase ZRANB3/AH2 can recognize K63-linked polyubiquitinated PCNA and plays an important role in restarting stalled replication forks.     

How to remake a fibroblast into a neural stem cell

In this issue of Cell Stem Cell and in a recent issue of PNAS, Thier et?al. (2012), Han et?al. (2012), and Lujan et?al. (2012) report the derivation of multipotent neural stem/progenitor cells from cultured mouse fibroblasts using distinct reprograming approaches.     

Lymphocyte choriomeningitis virus plays hide-and-seek with type 1 interferon

In this issue, Macal et?al. (2012); Walsh et?al. (2012), and Wang et?al. (2012) examine how adaptive immune responses to acute and chronic lymphocyte choriomeningitis virus infection are regulated by type 1 interferon produced early during infection by different cell types upon activation by intracellular nucleic acid sensors.     

The bionic retina: a small molecule with big potential for visual restoration

In this issue of Neuron, Polosukhina et?al. (2012) intravitreally deliver the light-activatable molecule acrylamide-azobenzene-quaternary ammonium (AAQ) to the eyes of mice with end-stage retinal degeneration. Results show that, with the appropriate illumination, AAQ restores light sensitivity and visual behavior.     

Early retinal activity and visual circuit development

Does spontaneous retinal activity prior to vision play a role in the establishment of visual maps? In this issue of Neuron, two separate papers by Huberman et al. and Hooks and Chen demonstrate a role for early spontaneous retinal activity in the establishment of ocular dominance columns and synaptic refinement at retinogeniculate synapses.     

Fear of the Light or Need for Action: The IGL Will Judge

Temporal adaptation of behaviors is of crucial importance for every organism. In this issue of Neuron, while?elegantly establishing the developmental program of the subcortical visual shell (SVS), a group of retinorecipient nuclei, Delogu et?al. (2012) also implicate one of its structures, the IGL, as a potential important player in the regulation of daily activity pattern.     

Cullin RING Ligases: Glommed by Glomulin

Cullin ring ligases (CRLs) constitute the largest group of RING finger ubiquitin ligases. Two recent studies in?Molecular Cell describe glomulin as a CRL1 inhibitor that blocks interactions with its ubiquitin-conjugating enzyme (E2) (Duda et?al., 2012; Tron et?al., 2012). These findings and their significance are discussed.     

S1P(1) Bridges Mechanotransduction and Angiogenesis during Vascular Development

Mechanisms of stabilization of the vascular plexus and the role of mechanotransduction in this process are?not well understood. In this issue of Developmental Cell, Jung et?al. (2012) and Gaengel et?al. (2012) describe the ligand-sensitive and mechanosensitive functions of an important vascular G protein-coupled receptor, S1P(1).     

Disintegrating brain networks: from syndromes to molecular nexopathies

In this issue of Neuron, Raj et?al. (2012) and Zhou et?al. (2012) use graph theory to suggest that neurodegenerative diseases spread diffusively via intrinsic brain networks. These studies provide a powerful model for understanding and predicting disease-specific profiles of neurodegeneration.     

The mitochondrial pyruvate carrier: has it been unearthed at last?

The mitochondrial pyruvate carrier (MPC) is essential for several major pathways of carbohydrate, fat, and amino acid metabolism, yet its molecular identity has remained elusive. Two recent papers in Science (Herzig et?al., 2012; Bricker et?al., 2012) implicate three newly identified inner mitochondrial membrane proteins as MPC components.     

Hijacking leucyl-tRNA synthetase for amino acid-dependent regulation of TORC1

TORC1 activity in all eukaryotes is dependent on amino acid availability. However, the mechanism through which TORC1 senses amino acids is still a mystery. In the current issues of Molecular Cell and Cell, Bonfils et?al. (2012) and Han et?al. (2012) implicate leucyl-tRNA synthetase in this evolving story.     

Unwinding to recombine

The MCM proteins are best known for their role in DNA replication, MCM2-7 forming the replicative helicase. Now, two reports in this issue of Molecular Cell, Nishimura et?al. (2012) and Lutzmann et?al. (2012) show the less well understood MCM8 and MCM9 to be crucial for effective homologous recombination.     

TXNIP Switches Tracks toward a Terminal UPR

During the progression of diabetes, crosstalk between ER stress and inflammation controls islet cell fate. In this issue, Lerner et?al. (2012) and Oslowski et?al. (2012) discover that thioredoxin-interacting protein (TXNIP) is a regulatory switch connecting the terminal unfolded protein response (UPR) and NLRP3 inflammasome to mediate β cell death.     

A neural circuit model forming semantic network with exception using spike-timing-dependent plasticity of inhibitory synapses

We propose a neural circuit model forming a semantic network with exceptions using the spike-timing-dependent plasticity (STDP) of inhibitory synapses. To evaluate the proposed model, we conducted nine types of computer simulation by combining the three STDP rules for inhibitory synapses and the three spike pairing rules. The simulation results obtained with the STDP rule for inhibitory synapses by Haas et al. [Haas, J.S., Nowotny, T., Abarbanel, H.D.I., 2006, Spike-timing-dependent plasticity of inhibitory synapses in the entorhinal cortex. J. Neurophysiol. 96, 3305–3313] are successful, whereas, the other results are unsuccessful. The results and examinations suggested that the inhibitory connection from the concept linked with an exceptional feature to the general feature is necessary for forming a semantic network with an exception.     

Transmitter time: synaptic plasticity and metabolic memory in the hypothalamus

Hunger elicits feeding behavior by activating Agouti-related peptide (AgRP) neurons. Two recent studies show how fasting, or the hunger hormone ghrelin, promote excitatory glutamate release onto AgRP neurons (Yang et?al., 2011) and increase postsynaptic glutamate receptor-mediated drive (Liu et?al., 2012).     

A tale of timing and transport

Excitatory and inhibitory synapses show long-term plasticity, but spike timing-dependent plasticity was seen only at excitatory connections. No longer. In this issue of Neuron, Woodin et al. demonstrate that coincident pre- and postsynaptic activity acts on the neuronal K+/Cl- cotransporter KCC2 to shift the reversal potential for Cl- and thus alters the effectiveness of GABAergic synapses.