This document discusses nitrogen uptake and transport in plants. It notes that nitrogen is essential for plant growth and development, and that plants take up nitrogen from the soil in nitrate and ammonium forms via transporters and channels. It describes several important nitrate and ammonium transporters in plants, including NRT1, NRT2, CLC and AMT transporters. It also discusses the nitrate signaling pathway in regulating nitrogen demand and the roles of transporters in distributing nitrate within plants and remobilizing it from older to younger tissues. While many transporters have been identified and characterized, further study is still needed to understand the functions of all nitrogen transporters and how they coordinate nitrogen acquisition and signaling in response to environmental