Expression of endogenous genes by non-homologous recombination of a vector construct with cellular DNA

摘要

Activating gene expression or causing over-expression of a gene by recombination methods in situ is disclosed. Also disclosed are methods for expressing an endogenous gene in a cell at levels higher than those normally found in the cell. In one embodiment of the invention, expression of an endogenous gene is activated or increased following integration into the cell, by non-homologous or illegitimate recombination, of a regulatory sequence that activates expression of the gene. In another embodiment, the expression of the endogenous gene may be further increased by co-integration of one or more amplifiable markers, and selecting for increased copies of the one or more amplifiable markers located on the integrated vector. Also provided are methods for the identification and expression of genes undiscoverable by current methods since no target sequence is necessary for integration. The invention also provides methods for isolation of nucleic acid molecules (particularly cDNA molecules) encoding transmembrane proteins, and for isolation of cells expressing such transmembrane proteins which may be heterologous transmembrane proteins. The invention also relates to isolated genes, gene products, nucleic acid molecules, and compositions comprising such genes, gene products and nucleic acid molecules, that may be used in a variety of therapeutic and diagnostic applications. Thus, endogenous genes, including those associated with human disease and development, may be activated and isolated without prior knowledge of the sequence, structure, function, or expression profile of the genes.