(New throughout)

NEW YORK, April 25 (Reuters) - E*Trade Financial Corp (ETFC.O: Quote, Profile, Research) disclosed on Friday the resignations of Chief Financial Officer Robert Simmons and general counsel Arlen Gelbard, the latest senior executives to leave the online brokerage which has struggled with heavy mortgage losses.

Simmons will resign by May 9, while Gelbard resigned effective April 22, E*Trade said.

Matthew Audette will be acting CFO while the company looks for a permanent replacement. Audette, 33, has been E*Trade's controller and executive vice president since July 2005.

Russell Elmer, who served as E*Trade's general counsel for six years before resigning in June 2007, was named general counsel on an "extended interim basis," E*Trade said.

Simmons became CFO in January 2004, E*Trade said.

The changes are the latest of several since last November, when E*Trade agreed to sell an 18 percent stake and $3 billion of troubled securities to hedge fund Citadel Investment Group for about $2.55 billion.

Former Chief Executive Mitchell Caplan was ousted that month, and Donald Layton, a former vice chairman of JPMorgan Chase & Co (JPM.N: Quote, Profile, Research), became E*Trade's chairman. Layton added the chief executive role in March.

Also in March, E*Trade announced the resignation of R. Jarrett Lilien as chief operating officer, effective May 16.