The invention is generally directed to modified filamentous fungal host cells comprising one or more nucleic acids encoding one or more polypeptides under the control of one or more promoters that are functional in said cells. Methods of using the modified cells to express one or more polypeptides are also disclosed, including methods of screening cells transformed with one or more expression vectors comprising nucleic acids derived from synthetic or genomic nucleic acids including, cDNAs. Methods of purifying one or more polypeptides or complexes comprising one or more polypeptides expressed in the modified cells, intended for use as substrates in structure/function studies, as therapeutic agents, as diagnostic reagents, or as human or animal vaccines, are also disclosed.