* Nikkei falls 0.9 pct, Topix down 0.7 pct * Real estate and construction sectors lead losses * NTT DoCoMo up on iPhone hopes * Many investors await U.S. jobs data, Olympics fate By Tomo Uetake TOKYO, Sept 6 (Reuters) - Japan's Nikkei average fell on Friday, snapping a four-day winning streak, hit by profit-taking in the real estate and construction sectors as investors awaited U.S. jobs data later in the day and a decision on the country's Olympic bid. The benchmark Nikkei fell 0.9 percent to 13,942.11 by mid-morning after advancing 0.1 percent to 14,064.82 on Thursday. It rose 5.1 percent over the past four trading days. "Investors have quickly moved to lock in profits as Madrid was reported as a favoured candidate for the Olympic bid," said Kyoya Okazawa, head of global equities and commodity derivatives at BNP Paribas in Tokyo. "Since real estate and construction shares recently gained on hopes that Tokyo will win the race to host the 2020 Summer Olympics, it's only natural that some investors want to close the game now. I won't be surprised if the Nikkei shed 2 percent later in the session." Spanish newspaper El Mundo on Thursday published names of up to 50 International Olympic Committee members who were going to vote for them. Tokyo is competing against Madrid and Istanbul in the race to host the Games, and a decision is expected on Saturday. The real estate sector fell 2.3 percent and was the worst sectoral performer. Mitsui Fudosan Co, which is a leading developer in the Tokyo Bay area and has a number of buildings containing hotels, slumped 2 percent. Its peers Mitsubishi Estate Co Ltd and Tokyo Tatemono Co Ltd dropped 1.5 percent and 2.9 percent, respectively. Among the construction sector, Taisei Corp, which is the likely contractor for the new National Stadium, slumped 5.2 percent. Rivalling Kajima Corp, Obayashi Corp and Shimizu Corp falling between 3.2 percent and 3.5 percent. NTT DOCOMO OUTPERFORMS ON IPHONE HOPES Bucking overall weakness, NTT DoCoMo Inc briefly climbed as much as 3.8 percent to a 3-1/2-month high after sources familiar with the matter said Japan's largest mobile carrier will begin selling Apple Inc's iPhone as early as this autumn. DoCoMo has been the only major mobile carrier in Japan that does not offer the iPhone. The stock last traded 0.3 percent higher on the day and was the most traded stock on the main board. The news weighed on shares of rivals KDDI Corp and SoftBank Corp, which already offer iPhones, as they have been chipping away at DoCoMo's market share. SoftBank lost 2.2 percent, while KDDI eased 0.3 percent. The broader Topix was down 0.7 percent to 1,149.66. Trading was fairly light by mid-morning, with volume on the Topix at 28.6 percent of its full daily average for the past 90 days. The benchmark Nikkei is up 34 percent this year, but is down 13 percent since its May peak.