| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new protein which consists of a neutral amino acid transporter having a specific amino acid sequence and an amino acid sequence having mutation(s) in a part of the amino acid sequence, and is useful, for example for the analysis of transportation of drugs through the cell membrane and the blood tissue barrier. and for the development of antitumor medicines. SOLUTION: This protein is a new neutral amino acid trasnporter which consists, for example. of (1) a protein having an amino acid sequence shown by formula I, and (2) a protein having an ability of transporting neutral amino acids and their analogues in the presence of a protein which has an amino acid sequence which one or more amino acid(s) is/are deleted from, substituted, or added to the amino acid sequence shown by formula I, and has an amino acid sequence shown by formula II, or a protein consisting of an amino acid sequence which one or more amino acid(s) is/are deleted from, substituted, or added to. The protein is useful, for example, for the in vitro analysis of transportation of drugs through the cell membrane and the blood tissue barrier, and the development of selective antitumor medicines. |
