The subcellular organization of neocortical excitatory connections

ABSTRACT Understanding cortical circuits will require mapping the connections between specific populations of neurons1, as well as determining the dendritic locations where the synapses

occur2. The dendrites of individual cortical neurons overlap with numerous types of local and long-range excitatory axons, but axodendritic overlap is not always a good predictor of actual

connection strength3,4,5. Here we developed an efficient channelrhodopsin-2 (ChR2)-assisted method6,7,8 to map the spatial distribution of synaptic inputs, defined by presynaptic ChR2

expression, within the dendritic arborizations of recorded neurons. We expressed ChR2 in two thalamic nuclei, the whisker motor cortex and local excitatory neurons and mapped their synapses

with pyramidal neurons in layers 3, 5A and 5B (L3, L5A and L5B) in the mouse barrel cortex. Within the dendritic arborizations of L3 cells, individual inputs impinged onto distinct single

domains. These domains were arrayed in an orderly, monotonic pattern along the apical axis: axons from more central origins targeted progressively higher regions of the apical dendrites. In

L5 arborizations, different inputs targeted separate basal and apical domains. Input to L3 and L5 dendrites in L1 was related to whisker movement and position, suggesting that these signals

have a role in controlling the gain of their target neurons9. Our experiments reveal high specificity in the subcellular organization of excitatory circuits. Access through your institution

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OTHERS CORTICAL RESPONSE SELECTIVITY DERIVES FROM STRENGTH IN NUMBERS OF SYNAPSES Article 16 December 2020 INHIBITORY SPECIFICITY FROM A CONNECTOMIC CENSUS OF MOUSE VISUAL CORTEX Article

Open access 09 April 2025 TRANSLAMINAR SYNCHRONOUS NEURONAL ACTIVITY IS REQUIRED FOR COLUMNAR SYNAPTIC STRENGTHENING IN THE MOUSE NEOCORTEX Article Open access 03 February 2025 REFERENCES *

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Download references ACKNOWLEDGEMENTS We thank A. Karpova for help with viral constructs, G. Oliver and B. Xu for the Six3Cre mouse line, D. Chklovskii, G. Shepherd and Q. Wen for comments on

the manuscript, Y. Yu for the model of the dendrotoxin-sensitive potassium channel and T. O’Connor for software development. AUTHOR CONTRIBUTIONS L.P. and K.S. designed the experiments.

L.P. performed the experiments with help from T.M. (viral injections in M1 and related recordings). S.S. provided critical reagents. L.P. and K.S. analysed the data and wrote the paper.

AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia 20147, USA , Leopoldo Petreanu, Tianyi Mao, Scott M. Sternson 

& Karel Svoboda Authors * Leopoldo Petreanu View author publications You can also search for this author inPubMed Google Scholar * Tianyi Mao View author publications You can also search

for this author inPubMed Google Scholar * Scott M. Sternson View author publications You can also search for this author inPubMed Google Scholar * Karel Svoboda View author publications You

can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to Karel Svoboda. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION This file contains This

file contains Supplementary Methods, a Supplementary Discussion, Supplementary References, Supplementary Table 1 and Supplementary Figures S1-S9 with Legends Methods, a Supplementary

Discussion, Supplementary References, Supplementary Table 1 and Supplementary Figures S1-S9 with Legends (PDF 3903 kb) POWERPOINT SLIDES POWERPOINT SLIDE FOR FIG. 1 POWERPOINT SLIDE FOR FIG.

2 POWERPOINT SLIDE FOR FIG. 3 POWERPOINT SLIDE FOR FIG. 4 RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Petreanu, L., Mao, T., Sternson, S. _et al._

The subcellular organization of neocortical excitatory connections. _Nature_ 457, 1142–1145 (2009). https://doi.org/10.1038/nature07709 Download citation * Received: 19 August 2008 *

Revised: 04 December 2008 * Accepted: 18 January 2009 * Published: 26 February 2009 * Issue Date: 26 February 2009 * DOI: https://doi.org/10.1038/nature07709 SHARE THIS ARTICLE Anyone you

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