RT Journal Article SR Electronic T1 High-throughput mapping of long-range neuronal projection using in situ sequencing JF bioRxiv FD Cold Spring Harbor Laboratory SP 294637 DO 10.1101/294637 A1 Xiaoyin Chen A1 Yu-Chi Sun A1 Huiqing Zhan A1 Justus M Kebschull A1 Stephan Fischer A1 Katherine Matho A1 Z. Josh Huang A1 Jesse Gillis A1 Anthony M Zador YR 2019 UL http://biorxiv.org/content/early/2019/07/30/294637.abstract AB Understanding neural circuits requires deciphering interactions among myriad cell types defined by spatial organization, connectivity, gene expression, and other properties. Resolving these cell types requires both single neuron resolution and high throughput, a challenging combination with conventional methods. Here we introduce BARseq, a multiplexed method based on RNA barcoding for mapping projections of thousands of spatially resolved neurons in a single brain, and relating those projections to other properties such as gene or Cre expression. Mapping the projections to 11 areas of 3579 neurons in mouse auditory cortex using BARseq confirmed the laminar organization of the three top classes (IT, PT-like and CT) of projection neurons. In depth analysis uncovered a novel projection type restricted almost exclusively to transcriptionally-defined subtypes of IT neurons. By bridging anatomical and transcriptomic approaches at cellular resolution with high throughput, BARseq can potentially uncover the organizing principles underlying the structure and formation of neural circuits.