This family consists of several REV proteins from Borrelia burgdorferi (Lyme disease spirochete). The function of REV is unknown although it known that gene is induced during the ingesting of host blood suggesting a role in the metabolic activation of borreliae to adapt to physiological stimuli [1].

1: Analysis of Borrelia burgdorferi gene expression during life cycle phases of the tick vector Ixodes scapularis. Gilmore RD Jr, Mbow ML, Stevenson B; Microbes Infect 2001;3:799-808. PMID:11580974