In AND part, we utilized the GI-GAL4 and LOV-VP16 genes regulated by the GIP promoter (a glucose sensitive promoter that promotes the activity of the GIP promoter when glucose concentration increases), as well as the insulin gene regulated by the UAS promoter (which can be activated by GAL4-VP16). When the glucose concentration increases, GI-GAL4 and LOV-VP16 proteins are expressed. When the glucose concentration rises to a pathological state, blue light will be accurately activated to catalyze the covalent binding of GI-GAL4 and LOV-VP16 proteins, thereby assembling into active GAL4-VP16 transcription factors that bind to the UAS promoter to promote insulin synthesis and secretion.

The AND part plays a more precise role in regulating insulin synthesis, but the half-life of GAL4-VP16 protein reaches the hour level, and the undecomposed protein continues to promote insulin synthesis, thereby posing a risk of hypoglycemia. To avoid this situation, we have designed a NOT part. The system consists of miRNA and miR-BS (miRNA binding site) located in the insulin expression vector 3 '- UTR. When miRNA is expressed, it binds to miR-BS and inhibits insulin expression. In order to prevent the NOT part from blocking normal insulin secretion, we further constructed a GIP promoter controlled sponge. Under high blood sugar conditions, the sponge binds to miRNA, releasing miRNA's binding to insulin expression. However, when blood sugar drops to normal, the expression of the sponge decreases, and miRNA binds to miR-BS, inhibiting insulin expression.