Nina Sky’s double moves

A hot single with a cool groove can ignite any summer dance floor, and teenage twin-sister act Nina Sky is blowing things up in clubs, on the charts and on MTV with “Move Ya Body,” their sultry debut track that blends hip-hop and a Jamaican dancehall rhythm known as the “Coolie Dance.”

That beat is itself becoming a fad, heard on many hip numbers. But on Wednesday at the El Rey Theatre, Queens-born Nicole and Natalie Albino, 18, showed some potential staying power with their down-to-earth charisma and flashes of vocal talent.

Their debut album, “Nina Sky” -- massaged by the usual army of producers and song doctors -- displays a sense of sonic adventure and an assertive sexuality. At its best it’s Tweet lite, and that’s not bad. Unfortunately, their 25-minute headlining set only occasionally tapped those feelings, as with the R&B-tinged; “Your Time,” a wistful request for a boyfriend’s undivided attention, and the talk-to-the-hand non-album track “Time to Go,” an answer to Mario Winans’ cheating-heart hit “I Don’t Wanna Know.”

Backed by a turntablist and two bouncing male dancers, the pair sang sweetly and rapped unremarkably, and Nicole played some guitar. But their act already is riddled with cliches -- all the hands-up, holla-back hoopla that’s as ritualistic in hip-hop as lighter-flicking is in rock. And when the time came to “Move Ya Body,” they pulled a little girl from the audience on stage, a miscalculation that rather diluted the steamy vibe.