Motricity, a fast-growing global provider of mobile content applications for telecommunications providers, announced Tuesday that it would lay off much of its Durham work force and move its headquarters to Washington state.

Motricity plans to eliminate 250 jobs over the next nine months, most of which will be among its 350 Durham employees. The affected employees will be given 60 days’ notice before their jobs are eliminated and severance packages.

The moves are part of a consolidation of two companies: Motricity and the mobile information business unit of InfoSpace, which Motricity acquired for $135 million in January.

The InfoSpace group is based in Bellevue, Wash., and the company said in a statement that Washington would serve as a better base because of its proximity to some of the company’s larger customers.

Company spokesman Les Hamashima also said the West Coast has more workers experienced in mobile application software development than the Triangle. He said North Carolina has plenty of technology workers, but the specific skill set needed by Motricity is more prevalent elsewhere.

Motricity will maintain a small operation in Durham, but it will either move to different office or sublet most of the 70,000 square feet it leases in the American Tobacco Complex in downtown Durham, officials said.

Ryan Wuerch, a co-founder of Motricity, will remain the chairman and chief executive officer of the combined company. Steve Elfman, who had been executive vice president for the InfoSpace unit, will serve as Motricity’s president and chief operating officer.

Elfman at one time was chief information officer at AT&T.

Only a handful of key managers have been asked to move from Durham to Bellevue, officials said.

“The steps we’re taking to quickly integrate the two companies will position us very well for accelerated growth, while offering greater discipline and a more focused approach for our customers," Wuerch said in a statement. "While these decisions are always tough, we’re doing what is necessary to position Motricity for long-term and profitable growth.”

As part of the merger, billionaire Carl Ichan and other venture capital investors poured $185 million into Motricity. Privately held Motricity has considered going public, and the InfoSpace buy was seen as part of a growth strategy destined to make it more appealing to Wall Street.

But the combination of the two companies created one entity with more than 650 workers – and significant duplication of effort. Rumors had been circulating within the company for weeks that substantial layoffs would be made.

In December 2006, Motricity cut its work force by 16 percent, or 50 employees, as it streamlined operations to focus more on content applications rather than producing and selling content.

Motricity also announced plans to discontinue non-profitable and non-core businesses, such as its direct-to-consumer property, Pocketgear.com, and divest some business relationships in the media and entertainment arena. In December, the company said it would sell eReader.com, another direct-to-consumer business, to a New Jersey firm.