Joan Osborne made her mark with the 1995 smash pop hit “One of Us” -- you know, the one about God riding the bus.

Now, it’s Osborne riding the bus. The Dixie Chicks tapped her to open the first 28 concerts of their Top of the World tour, which began in Greenville, S.C., on May 1.

“I have no idea why they called me for the gig,” Osborne confesses in a phone conversation two days before the tour started. “I’ve never met them. I don’t know them personally.”

So, why did she accept the invitation?

“Well, I just really like them and I like their music,” she says. “I like the fact that they really play all their own instruments, and it’s a really cool band. I don’t know, I just felt like it would be a great audience for me to get more exposure. I have something of an Appalachian country influence in my music, and I thought it would be an interesting challenge to play for that audience.”

Eight years after “One of Us” brought her international stardom and a Rolling Stone cover, many people still remember the song. And while she may be considered by some to be a one-hit wonder, she’s far from a has-been. In fact, her husky, sensual vocals are still in demand in nearly every musical genre.

Earlier this year, Osborne toured France, Portugal and Spain to support her latest album, How Sweet It Is, a collection of soul classics such as “I’ll Be Around” and “These Arms of Mine.” After that, she toured with the Funk Brothers, the studio musicians who played on nearly every Motown hit from 1959 to 1972. Osborne first appeared with them in the award-winning documentary Standing in the Shadows of Motown, turning in superb versions of “Heat Wave” and “What Becomes of the Broken Hearted.”

“When I would go out on stage every night, the groove felt like lying in a big feather bed,” she says. “It was like a fantasy, of being able to pretend that I was a Motown chick singer from 1967.”

When her portion of the Top of the World tour wraps, she’s hopping on the bus with the Dead (formerly the Grateful Dead) who are sharing the bill with Willie Nelson and Bob Dylan for a few months. She’s also collaborating with dance music star DJ Spooky and writing material for an upcoming studio album, reuniting her with the production team behind her triple-platinum debut Relish.

“I don’t know what I’m doing right, but thank you to whatever force in the world is bringing all these offers to me,” she says with astonishment. “I feel really privileged.”

In various ways, country music has been edging into Osborne’s life since she moved from her hometown of Anchorage, Ky., to New York City.

“I always listened to rock music in high school -- the Eagles and the Rolling Stones, and the Who and the Pretenders,” she says. “I came to New York City to go to college and I fell into this whole blues and rhythm and blues and roots-rock music that was going on in the Lower East Side and the East Village at that time. That’s when I started singing and got an education through hearing the musicians who were playing in the blues clubs at that time. And also going out and buying records of people like Howlin’ Wolf and Etta James, Aretha Franklin and Tina Turner, and Otis Redding and all the great soul singers that came out of gospel-inspired soul and blues music.

“And as part of that, I also delved into more of the roots-country side of things,” she continues. “I learned about the Louvin Brothers, the Carter Family and people like that. It wasn’t really until I left Kentucky that I started having more of an appreciation for the music that came out of Kentucky, like Bill Monroe.”

Lately, she’s been listening to a lot of Dolly Parton and contributes an acoustic version of “Do I Ever Cross Your Mind” to Parton’s upcoming tribute album. (“I don’t think you can find anyone who doesn’t love Dolly Parton for one reason or another,” she says.)

“I’ve got a house in upstate New York, and when I go up there, there’s this one station that plays old-time country. Not like old-old, but from the ‘60s and ‘70s, and people like Tammy Wynette and Emmylou Harris. I always listen to that station when I’m up there. I’m starting to collect all these cool songs that I hear on that station, and who knows, maybe at some point I’ll do a record that’s inspired by that, or actually record those songs.”

Also citing George Jones, Gram Parsons and Hank Williams as personal favorites, she adds, “I’m a big Loretta Lynn fan. I love Loretta Lynn. I just think she’s amazing, not just as a singer, but as a writer as well. And as somebody who brought this very female perspective to country music. … I really have a lot of respect for her and it’s great that she’s still around and still touring. It’s wonderful that you can still go see Loretta Lynn on the road.”

Told that you can even go to Lynn’s house, Osborne laughs.

“I never have done that. Maybe next time in the area, I’ll do that.”

But in the meantime, there’s a tour to attend to.

“We’re not a straight-up country band, but we’re going to try to draw from that part of the music that I do that’s influenced by country, and we’re also going to do some straight-ahead rock ‘n’ roll,” she says. “Tell them to expect to get off their seats and dance a little bit. That’s what we’re going to try to do, get them nice and warmed up for the Dixie Chicks.”