Late in the larval stage, holometabolous insects produce and store hexamerins in the fat body for an important source of amino acids during metamorphosis. As the nutritional status of the late larva dictates its ability to complete metamorphosis and become a reproductively competent adult, nutrient signalling may play a role in the regulation of sex-specific hexamerin expression. The mosquito, Ochleratatus atropalpus synthesizes one hexameric storage protein, Hexamerin 1.2, which is unique to females. Hex-1.2 activity is fat body-specific, and restricted to the late fourth-instar female larva and young adult female. Putative binding sites for specific transcription factors, including Doublesex (DSX), suggest that the Hex-1.2 gene may share mechanisms for sex-specific transcription in the fat body with other insects. In Drosophila transformants, as little as 300 bp of the Hex-1.2 5’-flanking region, including the DSX binding sites, confer female-specificity to a lacZ reporter gene and may function as a sex-specific, tissue-specific enhancer. Further studies are ongoing to determine if Hex-1.2 activity is nutritionally regulated through the insulin response target of rapamycin (TOR) pathways.