When she turned seven, Johnson's family left Los Angeles and she spent time growing up in Phoenix, Arizona and later, Portland, Oregon.
While pursuing her degree, Johnson performed in a number of plays and was a member of the school's sketch and improv group, Comedy Corner.
[1] After college, Johnson moved back to Los Angeles and began studying at The Groundlings School and Theatre, whose alumni include fellow MADtv cast members Phil LaMarr, Michael McDonald, and Daniele Gaither.
[citation needed] Johnson has had recurring roles on Key & Peele, Reno 911!, and Andy Barker, P.I.. A few of her other television credits include guest-starring roles on Single Parents, Prime Suspect, Weeds, Curb Your Enthusiasm, Monk, CSI: Crime Scene Investigation, The Shield, Hannah Montana, and Hot in Cleveland.
[2] Johnson joined the cast of MADtv in 2005 as a feature performer and writer in the show's eleventh season.