The Big Bang Theory's Kaley Cuoco gets tearful as she receives a star on the Hollywood Walk of Fame

The actress – who plays Penny on the hit US comedy – brought along her husband, Ryan Sweeting, to the ceremony, as well as co-stars Jim Parsons (Sheldon), Johnny Galecki (Leonard), Simon Helberg (Howard), Kunal Nayyar (Raj) and Mellisa Rauch (Bernadette).

Big Bang creator Chuck Lorre also spoke at the event, which saw Cuoco, 28, appear on the verge of tears as her star was unveiled in a spot near the one awarded to her former 8 Simple Rules co-star John Ritter.

"I didn't write a speech, because I thought I would speak from my heart and I already started crying in the car on the way over here, so I got that out of the way," she joked to gathered friends and fans. "I still think they are going to call and say this was a mistake.

"All my friends and family know that I never get nervous, they've never seen me nervous and I think I've been nervous twice in my entire life and this is one of them. I've been nervous all week, I've had a stomach ache and I'm so overwhelmed with love and emotion and I'm truly touched, I never would have thought something like this would have happened."

Her co-stars had plenty of kind words, with Galecki – who dated Kuoco for two years – calling her "luminescent in every way," while Parsons added: "she's there for you, she never drops the ball and it's amazing."

"People will come from all around the world to urinate right there next to your star, it's going to be so incredible," quipped Helberg.

The Big Bang Theory is America's biggest comedy and is currently airing its eighth series (Thursdays at 8:30pm on E4) with two more seasons already given the green light by US network CBS.

http://www.youtube.com/watch?v=T9q24aP32gY