Sara Gilbert has signed up to be a series regular on The Big Bang Theory, it has been confirmed.

The actress's character Leslie Winkle was introduced in the CBS sitcom's first season, which saw her appear in three episodes as a love interest for Leonard Hofstadter, played by Johnny Galecki. Gilbert and Galecki previously appeared as husband and wife in Roseanne in the 90s.

Gilbert is still best known for her role as Roseanne's Darlene Conner, but has also appeared in a number of other high-profile shows in recent years, including 24, Will & Grace and ER. Additionally, she has had roles in short-lived sitcoms Twins and The Class.

The Big Bang Theory's second season begins on September 22 in the US.