The District’s top transportation leader said Wednesday that he will step down under the new mayor, a casualty and symbol of the outgoing Fenty administration’s entrepreneurial yet sometimes unpopular style. District Department of Transportation Director Gabe Klein said he received a letter from Mayor-elect Vincent Gray on Tuesday night asking him to resign. He will leave Jan. 1.

Turnover among Cabinet officials is not unusual when their leader loses an election. But Klein’s departure signals not just a change in personality and style, but a broader structural shift at DDOT. A replacement has not been named.