O diagrama de ligação de um sistema olfativo glomerular: mero acaso, fortuita necessidade ou design inteligente?

quinta-feira, maio 19, 2016

The wiring diagram of a glomerular olfactory system

Matthew E Berck Avinash Khandelwal Lindsey Claus Luis Hernandez-Nunez Guangwei Si Christopher J Tabone Feng Li James W Truman Richard D Fetter Matthieu Louis Aravinthan DT Samuel Albert Cardona 

Harvard University, United States; The Barcelona Institute of Science and Technology, Spain; Fly Base, United States; Janelia Research Campus, Howard Hughes Medical Institute, United States

Published May 13, 2016

Cite as eLife 2016;10.7554/eLife.14859


The sense of smell enables animals to react to long-distance cues according to learned and innate valences. Here, we have mapped with electron microscopy the complete wiring diagram of the Drosophila larval antennal lobe, an olfactory neuropil similar to the vertebrate olfactory bulb. We found a canonical circuit with uniglomerular projection neurons (uPNs) relaying gain-controlled ORN activity to the mushroom body and the lateral horn. A second, parallel circuit with multiglomerular projection neurons (mPNs) and hierarchically connected local neurons (LNs) selectively integrates multiple ORN signals already at the first synapse. LN-LN synaptic connections putatively implement a bistable gain control mechanism that either computes odor saliency through panglomerular inhibition, or allows some glomeruli to respond to faint aversive odors in the presence of strong appetitive odors. This complete wiring diagram will support experimental and theoretical studies towards bridging the gap between circuits and behavior.