Abstract: We claim a method of expression a thioredoxin-fused membrane protein comprising expressing said thioredoxin-fused membrane protein in a cell-free protein synthesis system in the presence of a non-ionic detergent. It is preferable that the fused membrane protein which is a highly hydrophobic protein, e.g., a G protein-coupled receptor, can be produced in a state being highly soluble and capable of forming a biologically active three-dimensional structure. Also, this invention provides a recombinant polynucleotide encoding said thioredoxin-fused membrane protein which is expressed in the cell-free protein synthesis system.

Abstract: To develop system technology for a high throughput in vitro synthesis reaction method for biopolymers such as proteins, RNA, and the like.

Abstract: A fusion protein of thioredoxin with a target protein is expressed in a cell-free protein synthesis system to thereby synthesize at least a part of the fusion protein as a soluble protein. It is preferable that the target protein is a highly hydrophobic protein such as a membrane protein. In particular, a membrane protein such a G protein-coupled receptor can be produced in a state being highly soluble and capable of forming a biologically active three dimensional structure. Also, provided a recombinant vector for producing such a membrane protein in a cell-free protein synthesis system.

Abstract: The present application provides a purified human protein, DNA fragment encoding the protein, expression vector for the DNA fragment, various cells transformed with the expression vector, and antibody against the protein. The purified protein in this invention is useful as a medicinal or as an antigen for manufacturing the antibody against the proteins. Further, the protein is useful as a search reagent for elucidating the intracellular protein network or as a protein source for screening such a protein as binding with a small molecule medicinal. The human cDNA of this invention is useful as a probe for gene diagnosis or as a gene source for gene therapy. Further, it can be also used as a gene source for mass production of the protein encoded by the cDNA. The expression vector being capable of translating in vitro or expressing the DNA within the host cell can be used for producing the human protein of this invention in vitro or within various host cells.

Abstract: Isolated cDNAs derived from mRNAs expressed in human cells are provided, as are DNAs and RNAs comprising their nucleotide sequences, and vectors for expressing the cDNAs. The cDNAs encode proteins which have functions similar to known proteins.