ANK1 and infection: Fig. 6C shows that cells treated MG132 accumulated significantly higher amounts of EF1α compared to untreated cells. When we measured mRNA level for EF1α by real time RT-PCR, EF1α transcripts slightly increased in infected cells up to 2 days after infection (Fig. 6D), indicating that EF1α protein levels were mainly regulated by post-translational control during the O. tsutsugamushi infection. Taken together, these results suggest that O. tsutsugamushi infection leads to a specific reduction of EF1α, potentially via secreted Ank proteins, via ubiquitination-dependent proteasomal degradation.