“Emily Owens M.D.” 9 tonight, CW

LOS ANGELES — Mamie Gummer is her mother’s daughter. And maybe that’s part of the problem.

She’s so aware that you’re so aware that her mother is Meryl Streep, it’s as if she has developed a stopwatch in her head ready to irritably clock the minute her 63-year-old mother will get mentioned — she’s noticeably tense and brief with her responses. But at 29, Gummer needn’t feel defined by the link.

The actress has managed to steadily establish her own identity since her tender debut in “Heartburn,” opposite her mother and Jack Nicholson, more than two decades ago. She now finds herself headlining her first TV series, “Emily Owens, M.D.,” on the CW, which premieres tonight.

“I’ve been the star of my own show forever — it’s just now people can tune in once a week to watch me,” she quipped.

That’s not to say Gummer is flashy. Yes, in this moment, hot pink lipstick tints her thin lips, and she’s wearing body-hugging blush leather pants while also navigating the sleek tiled floor of a hotel lobby in Ruthie Davis metallic stilettos, but the leggy actress is in promotion mode, ready for the obligatory photo shoot. Otherwise, she’s reserved.

“All this,” she said, referring to the media blitz that comes with heading a show, “is weird.”

Gummer, born Mary Willa and the second eldest of Streep’s four children, perks up when discussing the young adult drama. In it, she plays the title character: a shy, love-struck medical student who quickly realizes working at a big hospital is eerily similar to high school. Emily is awkward, passive and thinks too much — resulting in a lot of voice-over exposition.

“She was just sort of jumping around the page and at me,” Gummer said of the character. “It felt like a great opportunity to carry a show for myself — to play on a bigger level.”

Gummer, who studied theater at Northwestern University, had honed her stage persona in plays such as “Mr. Marmalade,” opposite Michael C. Hall, and “The Water’s Edge.”

“I think that if that’s your norm, then that’s what you do,” she said of wanting to be an actress. “There was no, like, bright and shiny spotlight that came down and hit me one day. The spotlight was all I ever saw.”

After a few small movie roles and a part in HBO’s 2008 Emmy-winning miniseries “John Adams,” Gummer gravitated toward television — partly, and surprisingly, for practical reasons: “I’m not going to lie to you. The last play I did in New York, I got paid $330 a week,” she said. “So I was like, ‘OK, I love this, but this can’t realistically sustain me.’”

She landed guest stints on CBS’ “A Gifted Man” and Showtime’s “The Big C.” But none played to her strength — quirkiness — quite like CBS’ “The Good Wife.”

“She’s so honest, so vulnerable, so raw,” said the show’s creator, Jennie Snyder Urman. “And that makes her so likable. She brings this sort of naivete to the role that is subtle and elegant. … When I think about her, I don’t think about her mom.”