As soft late-morning light streamed through old multipane windows, Annie Nimmo and Aaron Davies danced to "Ave Maria," a flowing ballet that had the pair moving as one. They, and three other dancers, were taking advantage of one of their last available rehearsals in studio space their troupe has occupied since before Lowertown became cool.

Ballet Minnesota and Classical Ballet Academy have called the Jax Building in St. Paul's increasingly hip Lowertown neighborhood home for 26 years. But, as they prepare this week for upcoming performances of "Sleeping Beauty" and the 28th annual Minnesota Dance Festival, their run in Lowertown is coming to an end. This longtime low-cost hub of Lowertown's arts scene has been sold and all the current tenants — dancers, sculptors, painters and photographers — must find new space. The new owners won't say what this once shabby-chic space will become, although some combination of sparkling new commercial and residential is expected.

If so, the Jax sale continues a redevelopment trend: Upscale restaurants, apartments and condos are opening in space that once was low-price and fit for studios, pricing the Bohemian artists' vibe right out of the neighborhood. Many longtime tenants, arts champions and some city officials worry that Lowertown may lose what made the area so desirable to begin with.

"It's the age-old thing. A long-neglected area and its cheap rents attract artists who need a lot of space but don't have a lot of money," said Andy Remke, who owns the nearby Black Dog Coffee and Wine Bar and has been in Lowertown for 17 years. "But then they get pushed out by the people who are drawn here. It's sad."

Cheryl Rist, co-founder of the academy and Ballet Minnesota, said she isn't sad to be moving. Their new space, on the West Side flats just across the river from downtown, has more space for costume storage and plenty of free parking for parents dropping off their children at ballet class. But there is no question that Lowertown is losing its artists' core, she said.

"It's leaving, slowly, no matter how much they say it's not … things that made it appealing, unfortunately, go away," Rist said.

Building tenants even held a "Jax Wake" a couple of weeks ago.

City Council Member Rebecca Noecker, whose ward includes Lowertown, said she has no desire to see that happen. It is exciting that new businesses, drawn by CHS Field, Union Depot and the Green Line, want to be part of the former warehouse district's resurgence, she said. With them comes increased tax revenue. But, she said, "we're in danger of killing the goose that laid the golden egg. The challenge is striking that balance between popularity and the culture of innovation and creativity that drew people here."

Noecker has teamed up with Joe Spencer, Mayor Chris Coleman's guy for arts and culture, and area artists to put their heads together to find possible solutions. They've had one meeting. More are planned.

While the city cannot subsidize rents to keep them affordable for artists, Noecker said, the city and artists' cooperatives can work to identify locations the cooperatives can buy to preserve as space for artists to live and work.

"Some sites might end up being across the river on the West Side," she said, because of lower rents there. "But we also want to keep the feeling in Lowertown that artists created here."

Groups like ArtSpace already own a couple of Lowertown buildings and foster art and artists, Remke said. The building occupied by Black Dog, the Northern Warehouse, has made it a priority to be artist-friendly and affordable. The coffee bar also has had a long relationship with area artists, displaying their work and hosting events. The love goes both ways. Remke said Andrew Rist of Ballet Minnesota once created and performed "The Black Dog Café."

Still, Remke said, as the neighborhood changes and becomes more upscale, "we feel some of the pressure, too. We have to increase our business to be more appealing to the people coming in."

But, he added, "We want to stay relevant to our longtime customers too. Somehow, we have to make it work. At the end, we don't want to be a nonprofit organization here. We have to pay our rent and pay our employees."

James Walsh • 651-925-5041