Mayim Bialik, who received an Emmy nomination for her work on “Jeopardy!” after the death of longtime host Alex Trebek, said on Friday that she would not return to the popular game show, leaving Ken Jennings as the sole host.

Bialik began hosting “Jeopardy!” on an interim basis in 2021, and on a permanent one last year. She has not appeared on the program or its “Celebrity Jeopardy!” offshoot for the past few months. In May, the entertainment news site Deadline reported that she had stepped away from “Jeopardy!” in solidarity with the Hollywood writers’ strike.

“Sony has informed me that I will no longer be hosting the syndicated version of Jeopardy!” Bialik wrote on social media on Friday, referring to the firm that produces the show. “I am deeply grateful for the opportunity to have been part of the Jeopardy! family.”

She did not mention the strike, which ended in the fall.

Sony confirmed Bialik’s departure in a separate statement, saying only that the decision for Jennings to continue alone was made “to maintain continuity for our viewers.” The company thanked Bialik for her contributions and said that it hoped to continue to work with her on prime time specials, without elaborating.

The shake up at “Jeopardy!” is the latest for a show that struggled to find a replacement for Trebek after his death in November 2020. Following a string of celebrity hosts, including LeVar Burton and Mehmet Oz, and a botched plan for executive producer Mike Richards to take over, Bialik filled in as a temporary host and split duties with Ken Jennings, a former champion.

Bialik, who has a Ph.D. in neuroscience and is best known for starring in “The Big Bang Theory,” a television show, made it clear when she stepped in as interim host in 2021 that she wanted the position to become permanent.

Some critics questioned her impartiality. Trebek had been celebrated for having a neutral and impartial air, while Ms. Bialik was outspoken on topics such as vaccines.

But in July 2022, Bialik and Jennings were named permanent joint hosts, and both were nominated this year for an Emmy for “Outstanding Host for a Game Show.”