TOKYO, Oct 10 (Reuters) - Japanese shares rose sharply on Tuesday, led by energy-related shares, as overnight gains on Wall Street boosted risk appetite and investors scooped up beaten-down stocks.

The Nikkei was up 2.49% to 31,766.75 by the midday break, on track to post its biggest daily gain since Jan. 18, if the gains hold.

The index fell to an over four-month low last week and posted its third straight weekly loss.

The broader Topix jumped 2.09% to 2,311.30 on Tuesday.

"Japanese shares were sold too heavily until last week," said Shuutarou Yasuda, a market analyst at Tokai Tokyo Research Institute.

"It was the time for a rebound and overnight gains in Wall Street supported investor sentiment. Easing U.S. Treasury yields was also a positive factor."

Energy explorers surged 9.1% as oil prices jumped overnight after military clashes between Israel and the Palestinian Islamist group Hamas ignited fears that a wider conflict could hit oil supply from the Middle East.

Refiners rose 6.02%.

Trading firms were also strong, with Sojitz and Itochu surging 8.44% and 7.13%, respectively, becoming the top gainers on the Nikkei.

All but two industry sub-indexes on the Tokyo Stock Exchange rose.

Airlines fell 1.56%, with Japan Airlines and ANA Holdings losing 1.77% and 1.40%, to become the worst performers on the Nikkei.

Yaskawa Electric rose 0.49% after the electrical equipment maker posted a rise in its half-year profit. The company is among the first to report results every season, and is widely viewed as a bellwether.

Of the 225 stocks on the Nikkei, 215 rose and 10 lost.

(Reporting by Junko Fujita; Editing by Mrigank Dhaniwala)