Importantly, HHO5 regulates plant gene expression genome-wide and plant growth in a nitrogen-dose dependent manner. “Inorganic nitrogen is taken up by plants from soil and assimilated into organic nitrogen. Notably, the plants lacking HHO5 absorbed nearly three times more nitrogen compared to plants with normal HHO5 levels in specific nitrogen conditions. This finding supports the idea that HHO5 signals organic nitrogen satiety and shuts down uptake of inorganic nitrogen from soil. NYU has filed a patent application covering the research and findings described in this paper to enable the improvement in plant nitrogen use efficiency.