Science-based R&D can deter venture capitalists due to high technical uncertainty. We study whether mission-oriented public funding, which supplies basic science as a public good, fosters VC investments. Our quasi-natural experiment is the BRAIN Initiative (BI), a government-funded program with the goal of mapping the human brain. Using a large language model, we first show the large spillover effects of BI in neurotech. In a difference-in-differences analysis, we find an increase in VC investments in neurotech startups accompanied by higher valuations and more successful VC exits following the BI. The channels driving these results suggest reduced technical uncertainty: 1) increased supply of high-skilled academic labor; 2) more innovation, including breakthrough patents; 3) enhanced integration with complementary technologies, especially AI and big data, which aligns with the BI's data-driven mission. Our results suggest the supply of government-backed science and scientists can spur follow-on private investments in emerging technologies.