Uab1 paternal imprinting requires Abd-B and Polycomb. G. Packert ¹, D.T. Kuhn ². 1) Sch Natural & Health Sci, Barry Univ, Miami Shores, FL; 2) Department of Biology, University of Central Florida, Orlando, FL.

   Paternal transmission of inversion Ultra-abdominal¹ (Uab¹) results in a gain of function of small patches of posterior abdominal and female genital tissue on more anterior abdominal segments. Genetic analysis demonstrated that trans interactions with Abdominal-B (Abd-B) on the Uab¹ homolog determines the penetrance and expression of these patches. The paternal effect is enhanced in the presence of mutations within the Uab¹ breakpoints and is eliminated when Uab¹is in trans with mutants or deficiencies lacking Abd-B function. Analysis of interactions between Uab¹and Polycomb (Pc) also show great enhancement of the gain of function phenotype. We discuss these finding with regard to Abd-B boundaries and Polycomb response elements.