HETEROLOGOUS EXPRESSION OF GENES IN BACTERIAL, FUNGAL, ANIMAL, AND PLANT-CELLS

Analysis of gene function is of central importance for the understandi ng of physiological processes. Expression of genes in heterologous org anisms has allowed the isolation of many important genes (e.g. for nut rient uptake and transport) and has contributed a lot to the functiona l analysis of the gene products. For animal research, expression in Xe nopus oocytes and cell cultures are predominant techniques, whereas in the plant domain, yeast has become the prevalent expression system. T his review provides a survey of this quickly developing field and inte nds to assist researchers in determining appropriate experimental appr oaches for specific biological questions. Because heterologous express ion technology is of special value for the analysis of proteins that; are difficult to handle biochemically, the examples given concentrate on membrane proteins, i.e. transporter proteins. Also included is a de tailed discussion of the functional expression methodology and its use in identifying and characterizing genes and proteins.