* All Topix's 33 subsectors in positive territory
* Bank shares outperform
* Takashimaya tumbles on disappointing forecast
By Ayai Tomisawa
TOKYO, April 13 (Reuters) - Japan's Nikkei share average rose to a new 1-1/2 week high on Wednesday morning after gains in Wall Street boosted sentiment, while a weaker yen triggered bargain-hunting on recently battered stocks such as automakers and bank shares.
The Nikkei soared 2.6 percent to 16,347.51 in midmorning trade, the highest since April 1.
The dollar was back above 108.50 yen, having climbed from a near 18-month trough around 107.63 set on Monday.
Wall Street gained on buying in energy shares supported by rising oil prices, before falling on profit taking in Asian morning trade. Brent crude dropped 27 cents to $44.32 a barrel as of 0207 GMT, after hitting a four-month high in the previous session.
As risk appetite returned, banks soared, with Mitsubishi UFJ Financial Group soaring 4.5 percent and Mizuho Financial Group surging 3.2 percent.
But traders said that such bargain-hunting rises may be short-lived as investors continue to worry about the volatile currency market.
"The most uncertain market now is the foreign exchange market, and Japanese stocks will likely be swayed by it for a while," said Takuya Takahashi, a strategist at Daiwa Securities.
Exporters were bought as well, with Toyota Motor Corp gaining 2.0 percent, Honda Motor Co adding 2.5 percent and Panasonic Corp advancing 2.2 percent.
While all of the Topix's 33 subsectors were in positive territory, department store operator Takashimaya Co tumbled 6.9 percent after it forecast a modest 3.1 percent gain in its operating profit for the year ending Feb 28, 2017, with net profit estimates nearly flat at 24 billion yen.
The broader Topix gained 2.2 percent to 1,327.43 and the JPX-Nikkei Index 400 rose 2.3 percent to 11,989.53.
Reporting by Ayai Tomisawa; Editing by Eric Meijer