Date of birth: June 14, 1960

Party: Democratic Party of Japan

Electoral district: Lower House; Tokyo No. 7 (fourth term)

Nagatsuma, who rose to prominence by uncovering the pension record-keeping fiasco while in the opposition camp, is staying on as health minister.

He broke the scandal that the government had lost records on 50 million public pension plans, earning him the nickname "Mr. Pension." But in the Hatoyama administration he turned cautious in his comments, mostly saying he was "examining the issues."

As promised in campaign pledges, Nagatsuma revived "single-parent aid," providing about ¥20,000 a month to single-parent households on welfare.

The allowances were halted in 2009 under the LDP.

He studied law at Keio University and worked at NEC Corp. before becoming a reporter for the Nikkei Business magazine.