Ichnoviruses (IV) occur in obligate symbiotic associations with endoparasitic Ichneumonid wasps. IVs are injected with eggs during parasitization, where viral infection and gene expression alter host physiology to ensure endoparasitoid survival and development. Our data represent ongoing investigations of the vankyrin gene family identified in the Campoletis sonorensis IV (CsIV) genome. The 7 vankyrin proteins of CsIV possess ankyrin repeat domains resembling the inhibitory domains of NF-κβ transcription factor inhibitors (Iκβs). These genes are divided into two subclasses: those (3 genes) expressed primarily in the host fat body (FB), and those (4 genes) expressed in host hemocytes (HC). Recent in vitro studies with plasmid-transfected Sf9 cells have revealed differences in protein localization patterns within and between the subclasses of CsIV vankyrins, suggesting that members of this gene family may be evolving to exhibit divergent physiological functions. When constitutively expressed in transfected Sf9 cells, the majority of CsIV vankyrins (3 HC; 2 FB) show predominant nuclear localization. The remaining two proteins (1 HC; 1 FB) localized predominantly to cytoplasmic granules. The two most closely related FB vankyrins (both nuclear) also exhibit different biological effects when expressed from recombinant AcMNPV baculoviruses in vitro. Insect cell lines infected with these recombinant viruses exhibit enhanced longevity compared to those infected with viruses expressing other vankyrins. We hypothesize that CsIV vankyrin proteins may differentially interact with NF-κβ mediated activities during immune responses and developmental cascades in parasitized hosts. Our current investigations are aimed at addressing the specificity and logistics of NF-κβ-vankyrin interactions in vitro.