SINGAPORE - A top lawyer, a business consultant, a non-profit director and a doctor will move from the backbench to become office-holders.

Marine Parade GRC MP Edwin Tong, who joined politics in 2011, will become Senior Minister of State for Law and Health from July 1.

Mr Tong, a Senior Counsel, will leave law firm Allen & Gledhill where he heads its litigation and dispute resolution department, as well as its restructuring and insolvency practice.

Meanwhile, Chua Chu Kang GRC MP Zaqy Mohamad, a 2006 General Election alumnus, will be Minister of State for National Development and Manpower.

The Ernst and Young partner is serving notice and will begin work at his two ministries on May 1, he told The Straits Times.

Two politicians from the Class of 2015 have been made senior parliamentary secretaries.

Ms Sun Xueling, chief executive of Business China, a non-profit organisation promoting bilingualism and biculturalism, will join the Home Affairs and National Development ministries.

She is an MP for Pasir Ris-Punggol GRC.

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Jurong GRC MP and oncologist Tan Wu Meng will join the Ministry of Foreign Affairs as well as the Ministry of Trade and Industry.

In a statement announcing changes to his Cabinet on Tuesday (April 24), Prime Minister Lee Hsien Loong also detailed new portfolios for seven existing office-holders.

Among the senior ministers of state, Mr Heng Chee How will move from the Prime Minister's Office to the Ministry of Defence, while Ms Sim Ann will take on the Communications and Information porfolio, continue in the Ministry of Community, Culture and Youth and relinquish her appointment in MTI.

Mr Chee Hong Tat will move to MTI and the Ministry of Education (MOE), and leave his roles at the Ministry of Communications and Information (MCI) and Ministry of Health.

Dr Janil Puthucheary will move to the Ministry of Transport, continue in MCI and leave MOE.

Dr Koh Poh Koon will leave the Ministry of National Development but continue as Senior Minister of State at MTI. On Monday, he was appointed deputy secretary-general of the National Trades Union Congress.

Minister of State Sam Tan will take on a new role at the Social and Family Development Ministry, continue in MFA and leave his appointments at the Prime Minister's Office and Manpower Ministry.

Senior parliamentary secretary Low Yen Ling will move to the Manpower Ministry, continue at MOE but leave MTI.