For Arcade Fire devotees, Regine Chassagne’s sparkly dresses — gold stripes and disco stardust at the Grammys, tarnished sequins atwirl on “Saturday Night Live” — are as much a signature as the band’s exuberant sound; even from the cheap seats, Chassagne shimmers. Get a little closer, and the finely wrought frocks, designed by the Montreal-based artist and fashion designer Renata Morales, 36, reflect another unique talent at work.

Born in Mexico City, Morales moved to Montreal 20 years ago. After graduating from art school, she went to work with a couture pattern maker and designed her first collection, in 1996, using hand-painted fabrics. By 2001 she had opened two boutiques, putting the young designer in the company of French Canadian fashion veterans like Denis Gagnon and Marie Saint Pierre. However, the labor-intensive pieces for which she became known were extremely challenging to manufacture, and as other artists began to approach her (she also works with Melissa Auf der Maur and Liela Moss from the Duke Spirit and was the costume designer for Denis Villeneuve’s Oscar-nominated short, “Next Floor”), Morales shifted her focus to custom work. “I’m concentrating on what I love doing most,” she says over coffee in her Old Montreal atelier, “which is the creative side.”

Using pleats and embroidery to create shape and rich textures, Morales transforms fabrics like tulle, velvet and wool into elaborate creations — say, cloth flowers or “bird-inspired craziness,” which she says is “really beautiful, but horrible to make.” Sequins are everywhere, covering an underbody layered with lace, inset into seams or adding a flapperesque vibe to an angular tulle skirt.

Morales says she will continue to create seasonal “collections” available by special order to her private clients. For spring 2012 she’s experimenting with an incredibly dense but surprisingly light, crochet-like texture she calls “mossy metal.” Added bonus: “You can twist [the pieces] into a bag and they’ll come out fine.”

And after costuming Arcade Fire’s forthcoming video “Sprawl II (Mountains Beyond Mountains),” Morales will introduce an online store featuring one-of-a-kind archival pieces. She describes the selection as “curated, with equal amounts of party glamour and sophistication”; prices range from $100 to $4,000, with most dresses in the $700 to $1,200 range. Befitting a true artiste, there is no set date for the site to go live, although the plan is for sometime this month. She says breezily: “It should be open after the Mercury retrograde.”