The chief executive of Japan Post Holdings Co. and the heads of two subsidiaries will resign to take responsibility for improper sales of insurance products that has prompted the government to plan the imposition of harsh penalties, sources close to the matter said Wednesday.Masatsugu Nagato, the 71-year-old CEO of the former state-owned postal services group, Japan Post Insurance Co. CEO Mitsuhiko Uehira, 63, and Japan Post Co. CEO Kunio Yokoyama, 63, plan to announce their resignations from their positions at a press conference on Friday, the sources said.The Financial Services Agency is …READ FULL ARTICLE