CAA has signed writer Rob Cohen. His credits include “The Simpsons,” “Saturday Night Live,” “The Big Bang Theory,” “Just Shoot Me” and “The Ben Stiller Show.” He is managed by Mosaic.Director Ben Steinbauer has signed with UTA. He recently directed the docu “Winnebago Man.” He is managed by Mosaic. Brillstein Entertainment has signed thesp Natasha Leggero. She stars in the upcoming “Comedy Central Presents” series on March 18. She continues to be represented by the Gersh Agency. Johnny Messner has inked with Zero Gravity Management. He has wrapped production on “She Wants Me” and “The Killing Game.” He is repped by the Gersh Agency.