Because Martha Plimpton has long been a friend of writer and activist Dan Savage, the actress was intrigued by the chance to star in “The Real O’Neals,” the new ABC sitcom (premiering at 7:30 p.m. Wednesday, WLS-Channel 7) loosely based on Savage’s own coming-of-age years in Chicago.

The actress and longtime member of the Steppenwolf Theatre ensemble was particularly attracted to delving into a sitcom that was inspired by Savage’s “relationship with his mother when he came out [as gay] as a young man.

“Having read a lot of Dan’s work and knowing the extraordinary relationship he had with his mother, I knew what an incredibly interesting, funny, witty and unique woman she was — and how important she was in his life. I wanted to explore that relationship and I wanted to explore the idea of a mother being resistant to her son’s coming out as gay, because of her faith and her fear for the fate of his immortal soul.”

On the show, Plimpton plays Eileen O’Neal, a devout Roman Catholic who comes to learn her youngest son Kenny (played by Noah Galvin) is gay, while dealing with a crumbling marriage to her Chicago cop husband, played by Jay R. Ferguson.

Asked if she pulled personality traits from women she has known over the years, Plimpton laughed and said, “I can describe that with one word: Absolutely!”

Yet simply playing the mother of a 16-year-old boy coming to terms with his homosexuality would not have been enough of a hook for her to sign on. After all, Plimpton has recently come off a successful five-season run in the Fox sitcom “Raising Hope.” She understands a thing or two about what makes a TV show attract an audience.

“There are a lot of factors, but universality is key. One of my favorite things about our writers is how they are exploring this boy’s coming-out and experiences as a young gay man. It is all about how universal they are. The experience of puberty, or falling in love for the first time, or finding a date for the prom, or knowing what you like, or knowing who strikes your fancy — these are all utterly normal parts of being a young person who is coming into your own,” said Plimpton.

“The fact that he’s a young gay kid experiencing all these normal rites of passage really delights me. It feels real. I don’t think we’ve seen this presented on television in quite this way before.”

Plimpton also is a firm believer in the concept that comedy often can be a subtle way to communicate serious issues. “Humor is and always will be a wonderful way to highlight things that we may be uncomfortable to talk about.”

She’s not shy about stressing that being gay for many young people is extremely difficult, even in today’s more accepting world. “A lot of kids are not accepted by their families when they come out. Something like 40 percent of homeless youth are LGBT,” said Plimpton. “That’s an incredibly hard and daunting number. We have a responsibility — as citizens, but also as people making this show — to respect that reality and offer people a way to talk about this and acknowledge their fears and weaknesses in a way that is loving.”

“The Real O’Neals” joins an ABC lineup that includes “The Goldbergs,” “black-ish” and “Off The Boat.” For Plimpton, “this group of shows highlights diverse experiences of different kinds of families being explored and encouraged. … In many ways it harks back to the great TV comedies of the ’70s that weren’t afraid to address the issues of the day. I hope we can meet that challenge in these equally challenging times.”