NFYB Integrates Hormonal Signals into Tissue Allometry by Promoting Protein Biosynthesis

ABSTRACT Tissue allometry is under precise hormonal control for achieving the appropriate body size and shape. While juvenile hormone (JH) and 20‐hydroxyecdysone (20E) coordinate insect growth and development, their roles in regulating tissue allometry remain unclear. During molting cycles in the American cockroach, we reveal that JH promotes early, drastic fat body expansion, whereas 20E stimulates late, rapid wing pad growth. Through transcriptomic screening of early and late fat body and wing pads across the last five nymphal instars, plus JH‐treated fat body and 20E‐treated wing pads, we identify NFYB as the central spatiotemporal factor gene. Mechanistically, by transcriptionally activating the core translational machinery, NFYB promotes protein biosynthesis of hexamerin storage compounds in the early fat body and minichromosome maintenance complex in the late wing pads. Our findings demonstrate NFYB as a spatiotemporin that integrates different hormonal signals into distinct tissue allometry, shedding light on how appropriate body shape is achieved in animals.