Synapse-specific connectivity and dynamics determine microcircuit function but are challenging to explore with classic paired recordings due to their low throughput.We therefore implemented optomapping,a~100-fold fast...Synapse-specific connectivity and dynamics determine microcircuit function but are challenging to explore with classic paired recordings due to their low throughput.We therefore implemented optomapping,a~100-fold faster two-photon optogenetic method.In mouse primary visual cortex(V1),we optomapped 30,454 candidate inputs to reveal 1,790 excitatory inputs to pyramidal,basket,and Martinotti cells.Across these cell types,log-normal distribution of synaptic efficacies emerged as a principle.For pyramidal cells,optomapping reproduced the canonical circuit but unexpectedly uncovered that the excitation of basket cells concentrated to layer 5 and that of Martinotti cells dominated in layer 2/3.The excitation of basket cells was stronger and reached farther than the excitation of pyramidal cells,which may promote stability.Short-term plasticity surprisingly depended on cortical layer in addition to target cell.Finally,optomapping revealed an overrepresentation of shared inputs for interconnected layer-6 pyramidal cells.Thus,by resolving the throughput problem,optomapping uncovered hitherto unappreciated principles of V1 structure.展开更多
基金supported by CIHR 295104,HBHL,FRQS 259572,and RBIQ 35450 fellowships.C.G.won NSERC USRA,FRQNT BPC,RI-MUHC,FRQS,and CIHR CGS-M studentships.K.E.B.was funded by IBRO.T.A.L.won the NSERC USRA.P.J.S.is funded by the MGH FoundationCFI LOF 28331+2 种基金CIHR PGs 156223,191969,and 191997FRSQ CB 254033NSERC DG/DAS 2024-06712,2017-04730,and 2017-507818。
文摘Synapse-specific connectivity and dynamics determine microcircuit function but are challenging to explore with classic paired recordings due to their low throughput.We therefore implemented optomapping,a~100-fold faster two-photon optogenetic method.In mouse primary visual cortex(V1),we optomapped 30,454 candidate inputs to reveal 1,790 excitatory inputs to pyramidal,basket,and Martinotti cells.Across these cell types,log-normal distribution of synaptic efficacies emerged as a principle.For pyramidal cells,optomapping reproduced the canonical circuit but unexpectedly uncovered that the excitation of basket cells concentrated to layer 5 and that of Martinotti cells dominated in layer 2/3.The excitation of basket cells was stronger and reached farther than the excitation of pyramidal cells,which may promote stability.Short-term plasticity surprisingly depended on cortical layer in addition to target cell.Finally,optomapping revealed an overrepresentation of shared inputs for interconnected layer-6 pyramidal cells.Thus,by resolving the throughput problem,optomapping uncovered hitherto unappreciated principles of V1 structure.
