Tokyo stocks rose slightly Tuesday morning as the yen’s weakening against the U.S. dollar lifted exporter issues, while investors were cautious ahead of U.S. economic data later this week. The 225-issue Nikkei Stock Average gained 86.93 points, or 0.22 percent, from Monday to 38,787.80. The broader Topix index was up 16.75 points, or 0.62 percent, at 2,732.74. The dollar briefly edged up to the lower 147 yen zone as the U.S. currency was sought amid reduced expectations for aggressive monetary easing by the Federal Reserve at its policy meeting later this month, dealers said. At noon, the doll…