Gene ‘Arc’ transports mRNA across cells and is required for some forms of plasticity

Also it appears to have evolved from viruses.

Elissa D. Pastuzyn, Cameron E. Day, Rachel B. Kearns, Madeleine Kyrke-Smith, Andrew V. Taibi, John McCormick, Nathan Yoder, David M. Belnap, Simon Erlendsson, Dustin R. Morado, John A.G. Briggs, Cédric Feschotte, Jason D. Shepherd. The Neuronal Gene Arc Encodes a Repurposed Retrotransposon Gag Protein that Mediates Intercellular RNA Transfer

James Ashley, Benjamin Cordy, Diandra Luci, Lee G. Fradkin, Vivian Budnik, Travis Thomson. Retrovirus-like Gag Protein Arc1 Binds RNA and Traffics across Synaptic Boutons



Computing with microtubules (Craddock, Tuszynski, Hameroff 2012)

This paper hypothesizes that postsynaptic CaMKII (calcium/calmodulin-dependent protein kinase II) receives synaptic input and then interacts with via phosphorylation, suggesting that memories may be encoded in the microtubules in this way. They note that the size and shape of CaMKII appears to be just right to phosphorylate the hexagonal lattices of tubulin proteins in microtubules. The paper also can “demonstrate microtubule-associated protein logic gates, and show how patterns of phosphorylated tubulins in microtubules can control neuronal functions by triggering axonal firings, regulating synapses, and traversing scale.”. Via ScienceDaily.

Travis J. A. Craddock, Jack A. Tuszynski, Stuart Hameroff. Cytoskeletal Signaling: Is Memory Encoded in Microtubule Lattices by CaMKII Phosphorylation? PLoS Computational Biology, 2012; 8 (3): e1002421 DOI: 10.1371/journal.pcbi.1002421.

Neuroscience as a new national priority

President Obama: “Now, it’s time to get to work.”

NYT article:


Single neurons can distinguish inward temporal sequences from outward

“activating synapses in a centrifugal sequence (outward from the soma) caused a different [lesser] [cortical pyramidal] neuronal response than activating the synapses in a centripetal (inward) sequence”

Alain Destexhe. Dendrites Do It in Sequences (24 September 2010)
Science 329 (5999), 1611.


Tiago Branco, Beverley A. Clark, and Michael Häusser. Dendritic Discrimination of Temporal Input Sequences in Cortical Neurons (24 September 2010)
Science 329 (5999), 1671.


Allen Institute for Brain Science adds human brain data

Expression data is now available for over 60K gene probes over the entire human brain. Click here to access this monster data set!

More info after the jump.

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First organism from entirely synthesized genome

Craig Venter has made a bacterium from an entirely synthesized genome (link is nice summary in WSJ). Here’s the paper in Science. Now, that that’s taken care of… who will be the first to design a “synthetic biological neural circuit”?


Dendritic organization of sensory input to cortical neurons in vivo

Jia, H., Rochefort, N., Chen, X., & Konnerth, A. (2010). Dendritic organization of sensory input to cortical neurons in vivo Nature, 464 (7293), 1307-1312 DOI: 10.1038/nature08947

Consider a a cortical neuron in V1, layer 2/3, whose output shows sharp orientation tuning. What are the orientation tunings of the most important inputs to that neuron? What is the spatial distribution of these inputs in the neuron’s dendritic tree?

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