Joshua Johnson

Joshua Johnson, who hosts “1A” on American University news/talk WAMU Washington (88.5) for NPR, is stepping down to join MSNBC. Johnson will host his final “1A” program on Dec. 20 and will join the cable news network in February 2020.

National politics reporter Todd Zwillich will temporarily host “1A” as a search for a new full-time host commences. Zwillich also serves as interim host of WNYC’s “The Takeaway.”