Matt Cullen will become the new CEO of Dan Gilbert's Bedrock real estate firm next week in one of a series of newly announced personnel shifts at Gilbert's family of Detroit-based companies, including the surprise departure of high-level executive Jim Ketai.

Cullen will take over effective Sunday, replacing Bill Emerson, who will remain in the family of companies as Quicken Loans' and Rock Holdings' vice chairman. Emerson is a former CEO of Quicken Loans, the mortgage giant that Gilbert founded in 1985.

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The leadership shuffle includes the departure of Ketai, who is stepping down as Bedrock's chairman "to pursue other opportunities" outside the Gilbert corporate family, according to a news release issued Thursday.

Ketai's departure follows that of former Bedrock executive Dan Mullen, who left the corporate family in early June to "pursue other interests."

Ketai cofounded Bedrock with Gilbert in 2011 and previously served as Bedrock's CEO and managing partner. Since that time, Bedrock has bought and developed more than 100 properties in greater downtown Detroit.

Gilbert, 57, returned to Michigan earlier this month following about two months of treatment in a Chicago rehabilitation center for a May 26 stroke. Few details have emerged about the businessman's recovery.

Cullen joined Gilbert's team in 2008 after 29 years with General Motors, where he was general manager of economic development and had handled GM's $500 million purchase and renovation of the Renaissance Center as the automaker's world headquarters.

“It is an incredible honor to begin working with the 600-plus passionate team members at Bedrock who, in just eight short years, have played such a significant role in driving Detroit’s new era of optimism and growth,” Cullen said in a statement. “With transformational developments currently underway throughout the city, and more big projects on the horizon, Bedrock will continue to be an engine for Detroit’s resurgence."

Cullen is currently a principal of Gilbert's corporate holding company, Rock Ventures, as well as CEO of Gilbert's casino gaming company, JACK Entertainment, which in May sold the Greektown Casino-Hotel in Detroit for $1 billion.

Cullen since 2003 also has served as chairman of the Detroit RiverFront Conservancy, a nonprofit entity that builds and operates the city's RiverWalk.

The new CEO of JACK Entertainment will be Mark Dunkeson, who also will become Bedrock's president and chief operating officer.

Other JACK executives joining Cullen and Dunkeson at Bedrock this year will include: