Tokyo stocks opened sharply lower on early Tuesday morning, tracking overnight tumbles of U.S. and European stocks and the yen's appreciation against the U.S. dollar. At 9:15 am, the 225-issue Nikkei Stock Average dropped 409.81 points, or 2.80 percent, from Monday to 14,209.32, after briefly slipping below 14,200 for the first time since Nov. 8. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was down 39.13 points, or 3.27 percent, at 1, 157.19. The U.S. 30-issue Dow Jones Industrial Average sank to a three- and-a-half-month low and the U.S. dollar temporarily fell to the upper 100 yen range, the lowest level since late November.