By Kantaro Komiya

TOKYO (Reuters) -Nissan Motor shares jumped as much as almost 21% on Tuesday after a filing showed activist investor Effissimo Capital Management had taken a stake in the struggling Japanese automaker.

In a regulatory filing on Monday, Nissan disclosed Cayman Islands-registered ECM Master Fund as a shareholder with a 2.5%stake as of end-September. ECM Master Fund is affiliated with Effissimo, according to SEC filings.

An Effissimo spokesperson could not immediately be reached for comment.

In a statement, the car maker said it appreciated all "existing and new shareholders that support and believe in the future potential of Nissan".

Nissan last week announced a plan to cut 9,000 jobs and 20% of its global manufacturing capacity amid a sales slump in China and the United States, slashing its annual profit outlook by 70%.

Nissan share price hit a four-year-low on Friday following the earnings results. It ended trade on Tuesday up 12.8% at 415.8 yen.

Shareholder activism has gained traction in Japan, where international and domestic investors are demanding firms to improve corporate governance and capital allocation at a record pace, also helped by regulators' guidance.

(Reporting by Kantaro Komiya; Editing by David Dolan)