Allison Herren Lee said she plans to step down as a commissioner at the Securities and Exchange Commission, creating a second vacancy atop Wall Street’s main regulator.

Lee, a Democrat, will stay at the watchdog until President Joe Biden names her successor and that person is confirmed by the U.S. Senate, according to a statement Tuesday. Her term is set to expire in June.

“Over the coming weeks and months, I will remain actively engaged in the commission’s critically important work, and I look forward to continued progress in advancing the commission’s regulatory agenda,” Lee said in the statement.

Lee, who has been a commissioner since 2019, served as acting chair of the agency last year during a period of wild trading in GameStop Corp. and other meme stocks that prompted calls for more rules. She has also played a key role in helping Chair Gary Gensler craft climate-change disclosure rules, which the SEC is slated to propose next week. Lee’s departure will leave a second open spot at the watchdog after Elad Roisman left a Republican seat vacant earlier this year.

This article was provided by Bloomberg News.