Genetic network shaping Kenyon cell identity and function in Drosophila mushroom bodies

Revealing the molecular mechanisms underlying neuronal specification and acquisition of specific functions is key to understanding how the nervous system is constructed. In the <i>Drosophila</i> brain, <u>K</u>enyon <u>c</u>ells (KCs) are sequentially generated to assemble the backbone of the <u>m</u>ushroom <u>b</u>ody (MB). <u>B</u>road-complex, <u>t</u>ramtrack, and <u>b</u>ric-ȧ-brac <u>z</u>inc <u>f</u>inger <u>t</u>ranscription <u>f</u>actors (BTBzf TFs) specify early-born KCs, whereas the essential TFs for specifying late-born KCs remain unidentified. Here, we report that Pipsqueak domain-containing TF <i>Eip93F</i> promotes the identity of late-born KCs by reciprocally regulating gene expression in main KC types. Moreover, <i>Eip93F</i> not only regulates the expression of calcium channel <i>Ca-α1T</i> in late-born KCs to functionally control animal behavior, but it also forms a genetic network with <i>BTBzf TFs</i> to specify the identities of main KC types. Our study provides crucial information linking KC-type diversification to unique function acquisition in the adult MB.