A picture of generosity: Artist comes to the rescue of Londongallery

Peter Doig's reputation was sealed 15 years ago by a show at the Whitechapel. Now he's returning the favour. Jonathan Brown reports

It has always been known as the artists' gallery, the place where students could hang their work alongside the most celebrated figures of their day. So perhaps it is only fitting that it is artists who will safeguard the future of the Whitechapel Gallery in the East End of London.

Next month, work donated by leading painters, sculptors and photographers from across the world will be auctioned to raise money for the 100-year-old gallery's expansion into the now-empty Whitechapel Library.

But perhaps the most exciting and important donation comes from the painter Peter Doig, a man who has steadfastly weathered the art world's changing fashions to become one of its most bankable and influential stars. The Scots-born painter has given a major work, entitled Charley's Space, valued at between £300,000 and £400,000, from his personal collection to raise money for the gallery that helped to seal his reputation 15 years ago.

This year, Doig became one of the few British artists to command a million-pound price tag for a work during their lifetime. The sale of Iron Hill, painted at about the same time as Charley's Space, sold at auction for £1.1m, elevating him to the six-figure club alongside artists such as David Hockney, Bridget Riley and Lucian Freud.

The Whitechapel auction, at Sotheby's in London on 13 October, will include an etching by Freud, as well as cast bronze sculpture by Rachel Whiteread and a Pharmaceutical-era work by Damien Hirst. There will also be pieces by the British artists Gary Hume and Gary Webb, as well as donations from the American photographers Cindy Sherman and Jeff Wall and a piece by the Austrian sculptor Franz West.

The oil-on-canvas is typical of Doig's eerie and carefully crafted imagery, which he typically draws from found objects as diverse as horror film stills and record covers. While all the participating artists acknowledge a debt to the White-chapel, it was recognition by the gallery in 1991 that brought Doig to international attention, and resulted in his nomination for the Turner Prize in 1995.

From his home in Trinidad, Doig said: "The Whitechapel was always the artists' gallery. A lot of artists have their studios in that area, and it used to be that mere upstarts - students - could show in the same gallery where the greats were having their shows. When I received an award from the gallery, I was chosen by an artist, and that choice was gone through by other artists. There was always that connection between artists."

Doig stuck steadfastly to the medium of paint throughout the 1990s when painters found themselves at odds with the cultural mainstream. At the exhibition to mark his award of the Whitechapel prize he did not sell a single work. But he was undeterred.

"I'm not the type of person who would stop doing something because it was not in fashion," he said. "But there were always people interested in painting, even though people might not have been actually buying paintings. It is still something that people discussed and made."

Francis Outred, a senior director at Sotheby's, said interest in the artist was now intense. "He wasn't part of the Young British Artist group and was quite separate from them. During the 1990s, painting was sidelined, but he went on championing it. He was resolutely unfashionable. But in the past four or five years not only has the value of his work risen in the market, but so has his influence on other young painters, and especially in art schools."

As fashion turned full circle, Doig was included in an exhibition called The Triumph of Paintingin London in 2005. Some of his influences come from Canada's Group of Seven artists, who pioneered the painting of the Canadian wilderness, where Doig spent much of his childhood.

The work to be sold will be on show in the library from 26 September until 8 October.