CDAN1 and infection: A study of the in vivo transcriptional response of L. monocytogenes in a mouse infection model showed 13 out of 17 VirR-regulated genes, including mprF and the dlt operon, to be upregulated, leading the authors to conclude that VirR is the second most important virulence regulator in L. monocytogenes, after PrfA [67].