This BRAIN Initiative Notice of Funding Opportunity (NOFO) is to scale up efforts for viral, non-viral, transgenic, and gene regulatory element screening technologies and create reagent resources to access brain cell types. This NOFO is part of the BRAIN Initiative Armamentarium for Brain Cell Access transformative project. Reagent development efforts will apply gene transfer, gene regulation, genome engineering, activity sensor/effector, and atlasing technologies for use in both genetically tractable and less tra...