RT Journal Article SR Electronic T1 In vivo pulse-labeling of isochronic cohorts of cells in the central nervous system using FlashTag JF bioRxiv FD Cold Spring Harbor Laboratory SP 286831 DO 10.1101/286831 A1 Subashika Govindan A1 Polina Oberst A1 Denis Jabaudon YR 2018 UL http://biorxiv.org/content/early/2018/03/22/286831.abstract AB This protocol describes a fluorescence birthdating technique to label, track and isolate isochronic cohorts of newborn cells in the central nervous system in vivo. Injection of carboxyfluorescein esters into the cerebral ventricle allows pulse-labeling of M-phase progenitors in touch with the ventricle and their progeny across the central nervous system, a procedure we termed FlashTag. Labeled cells can be imaged ex vivo or in fixed tissue, targeted for electrophysiological experiments, or isolated using Fluorescence-Activated Cell Sorting (FACS) for cell culture or (single-cell) RNA-sequencing. The dye is retained for several weeks, allowing labeled cells to be identified postnatally. This protocol describes the labeling procedure using in utero injection, the isolation of live cells using FACS, as well as the processing of labeled tissue using immunohistochemistry.