James R. Healey, USA TODAY

Mary Barra, 51, has been named the new CEO at General Motors, first time a woman will hold the top job at a major automaker.

She takes over Jan. 15 from Dan Akerson. He's been CEO and chairman of the GM board since Sept. 1, 2010. Akerson, 65, said he accelerated the transition by several months, after his wife recently was diagnosed with an advanced stage of cancer.

Barra is executive vice president of GM's global product development, purchasing and supply chain.

"I will leave with great satisfaction in what we have accomplished, great optimism over what is ahead and great pride that we are restoring General Motors as America's standard bearer in the global auto industry," Akerson said in a message to employees.

Akerson oversaw GM's return to the stock exchange as a public company with an initial public offering November 2010, as the big automaker emerged from its Chapter 11 bankruptcy reorganization. He has overseen some of the car company's most profitable quarters.

GM vehicles have vaulted up the awards ladder and reliability scales under Akerson. His training is in finance and engineering and he was a surprise pick. Akerson was derided at first for not being a "car guy."