Compositions and methods for conferring enhanced disease resistance in a fish are provided. Compositions include novel recombinant constructs that induce transgenic expression of anti-pathogenic polypeptides, including cecropin proteins or biologically active variants thereof, in a fish. Expression of the anti-pathogenic polypeptide is under the control of novel synthetic promoters, naturally occurring fish promoters, or biologically active variants thereof. Compositions of the invention also include transgenic fish cells, fish eggs, and fish, particularly catfish, having the recombinant constructs of the invention stably integrated within their genome. Methods for expressing a polypeptide of interest within a host cell are also provided, wherein expression is under control of the synthetic promoters of the invention.