* Market in state of significant anticipation - trader
* Nikkei volatility index hits more than 4-month high
* Sharp Corp nosedives on news it will be moved to 2nd section
By Ayai Tomisawa
TOKYO, June 24 (Reuters) - Japanese stocks see-sawed in extremely volatile trade on Friday morning as investors watched early results on Britain's vote on European Union membership, which showed an extremely tight contest between the Leave and Remain camps.
The Nikkei opened a tad higher, but fell as much as 3.0 percent to a one-week low of 15,757.37 in early trade when investors were spooked by the Leave campaign's lead at one point in Britain's referendum over whether to stay in the European Union.
At 0140 GMT, the Nikkei edged up 0.1 percent to 16,249.42.
"Results are coming from certain districts of the U.K. that actually are fairly skewed one way or the other, and there is huge volatility in the pound and in the yen. I think that sort of set the tone for the morning," said Stefan Worrall, director of Japan equity sales at Credit Suisse.
A YouGov online poll of nearly 4,800 people of respondents released shortly after polls closed found 52 percent voted to remain in the EU and 48 percent voted to leave, Joe Twyman, YouGov's head of political and social research for Europe, told Sky News.
On Friday, the Nikkei volatility index jumped to a more than four-month high of 39.25.
"The market is in a state of significant anticipation. This is certainly crimping liquidity today because there is not a lot of substantial transactions going on in the market where you have this extraordinary volatile event," Worrall said.
The British pound skidded to as low as 146 yen, down 7.6 percent on the day.
The dollar dropped to 104.88 yen, pulling well away from an early high of 106.875.
Exporters took a hit, with Toyota Motor Corp falling 4.0 percent, Honda Motor Co shedding 3.0 percent and Nissan Motor Co dropping 2.5 percent.
Banking stocks also tumbled as investors became risk averse. Mitsubishi UFJ Financial Group dropped 1.4 percent and Mizuho Financial Group declined 2.5 percent.
Meanwhile, Sharp Corp nosedived 15 percent after news it will be moved to Tokyo Stock Exchange's second section from the first section from August 1.
The broader Topix dropped 0.2 percent to 1,295.73 and the JPX-Nikkei Index 400 declined 0.1 percent to 11,711.16.
Editing by Sam Holmes