UPDATE 1-Wall Street Journal managing editor resigning -WSJ

(Updates with WSJ sourcing, details)

NEW YORK, April 21 (Reuters) - The managing editor of the Wall Street Journal is planning to resign his post, the Journal reported on its website on Monday.

Marcus Brauchli, who took the top job at the paper a year ago, could resign on Tuesday morning, according to Time magazine, which first reported he would step down, citing sources.

Brauchli is likely to stay with the company in a yet-to-be-determined role but a search is already under way for the next managing editor, Time reported a source as saying.

A Wall Street Journal spokesman declined to comment and Brauchli did not respond to attempts to seek comment.

Rupert Murdoch's News Corp (NWSa.N: Quote, Profile, Research, Stock Buzz) acquired the newspaper this year in its $5.6 billion takeover of Dow Jones.

Time said Brauchli had tried to forge a middle way between the paper's traditional journalists and News Corp's new vision.

His resignation could reignite worries about editorial independence that were voiced during Murdoch's takeover bid, when some staffers feared the Journal's reputation as the top U.S. business newspaper would be threatened if Murdoch became proprietor.

Brauchli's position has been in question since Murdoch appointed former Times of London editor Robert Thomson as publisher of the paper.