An IRAK-1 homolog (FpIRAK-1) was cloned from the red tail shrimp F. penicillatus. FpIRAK-1 was constitutively expressed in various tissues of F. penicillatus. The expression levels of FpIRAK-1 mRNA in the different tissues are responsive to WSSV and V. alginolyticus challenge. Gene knockdown of FpIRAK-1 enhanced the sensitivity of shrimps to WSSV and V. alginolyticus challenge.