On the cover: CLPP-knockout (KO) cells are protected from vesicular stomatitis virus (VSV) due to elevated activation of the cGAS–STING signaling axis. Pictured are CLPP-KO/STING-KO mouse fibroblasts, which are highly susceptible to infection with VSV. VSV-G envelope glycoprotein appears in green, and cell nuclei appear in blue. Torres-Odio, S., Y. Lei, S. Gispert, A. Maletzko, J. Key, S. S. Menissy, I. Wittig, G. Auburger, and A. P.West. 2021. Loss of mitochondrial protease CLPP activates type I IFN responses through the mitochondrial DNA–cGAS–STING signaling axis. J. Immunol. 206: 1890–1900.