Dr. Francis S. Collins, the longtime director of the National Institutes of Health who stepped down late last year to go back to his lab, now has a new title: acting science adviser to the president.

The White House announced Thursday that Dr. Collins will be one half of the team temporarily replacing Dr. Eric S. Lander, who served as the president’s science adviser and director of the White House Office of Science and Technology Policy until he resigned last week after apologizing for bullying his colleagues.

Alondra Nelson, the deputy director of the office and a former sociology professor at Columbia University, will “perform the duties” of the director. Both she and Dr. Collins will serve until permanent leadership can be found and confirmed by the Senate, the White House said.

Dr. Lander’s departure left a big hole in the Biden administration. The president ran on a promise of elevating science and research, and Dr. Lander had a broad vision. He was behind efforts including the expansion of the president’s cancer moonshot initiative and a pandemic preparedness plan that the president likened to the Apollo mission to the moon. He was also the first science adviser to be a member of the cabinet.

Dr. Collins, 71, a geneticist and a physician who ran the health institutes for 12 years under three presidents, will continue working in his lab at the National Human Genome Research Institute, a division of the N.I.H. that he led before becoming director. As acting science adviser, he will address a broad range of issues, including climate change and pandemic preparedness.

He will also be an acting co-chairman of the President’s Council of Advisors on Science and Technology, a high-powered group of experts in fields as diverse as agriculture, biochemistry, ecology and nanotechnology, created by the president in September to advise the White House on its approach to future pandemics, climate change and other global challenges.

Dr. Lander had been one of three co-chairs of the panel. The others are Frances Arnold, a Nobel Prize-winning biochemical engineer, and Maria T. Zuber, a geophysicist and planetary scientist who was the first woman to lead a NASA planetary mission.