The planned conversion of Gaylord Entertainment to a real estate investment trust will cost more than 300 headquarters employees their jobs with the company.

Gaylord officials on Tuesday notified the workers that their time with the Nashville-based company will end after Sept. 30, assuming the $210 million planned sale of the Gaylord Hotels brand and management rights to Marriott International goes through. (Gaylord is fending off opposition from TRT Holdings, its largest shareholder.) Of the 310 affected employees, about 120 will shift to Marriott's payroll.

"As we expressed during May’s press announcement, this is an extremely difficult and unfortunate part of the reorganization process as the company prepares to sell the Gaylord Hotels brand and the rights to manage its four hotels," the company said in a statement. "We are committed to assisting all of our impacted STARS with outplacement services as they transition to new employment."

Word of the layoff notices comes a day after Gaylord officials detailed in a regulatory filing that they have set aside $19 million in severance and retention payments related to the Marriott sale and REIT conversion. Spokesman Brian Abrahamson said Tuesday afternoon that he did not know how much of that figure would be available to those being laid off.

Shares of Gaylord (Ticker: GET) ended Tuesday trading at $36.73, down slightly on the day. They're up more than 50 percent this year.