Unknown artist's exhibition illustrates the enduring influence of Charles Saatchi

Annie Kevans is a relatively unknown and struggling artist who lives in a council flat, works part time as a secretary and puts in long hours at her studio in London's East End. But her fortunes could be about to change with the opening this week of the first solo show of her paintings at a small gallery in Shoreditch.

Kevans, like Tracey Emin before her, is one of the young artists whose careers have benefited from the patronage of Charles Saatchi, arguably Britain's most important art collector.

Although his gallery at County Hall closed amid acrimony last December and his new exhibition space in London will not open for another year, the progress of Saatchi-endorsed artists such as Kevans, Conrad Shawcross and Toby Ziegler (see box) suggests that his influence on the contemporary art world remains as strong as ever.

Despite the lack of anywhere to display his unrivalled private collection of modern art and suggestions that he has lost his touch for spotting the next generation of art superstars, Mr Saatchi is still exhibiting work online and, more importantly, is still personally trawling small galleries and exhibitions, as well as the degree shows of the art colleges, and buying obsessively.

Karen Wright, the editor of Modern Painters magazine said: "He's looking for new material for his gallery. Mr Saatchi wants to demonstrate that he is still around. He leads with his eyes and collecting is a personal passion."

Kevans, she said, was only one of many artists bought recently by Mr Saatchi. "Philip Ziegler is very talented and Shawcross is an almost certain nominee for the Turner Prize in the future.''

Although Mr Saatchi often picks up such works relatively cheaply, his patronage alone can lead to an artist's prices rising, often allowing him to make a substantial profit later on.

Whether or not Kevans eventually achieves a status comparable to Emin or Damien Hirst, now said to be worth £100m, artistic immortality is likely to remain out of reach. Mr Saatchi has said that most contemporary artists will be viewed as footnotes by history and that most installation art "ends up rotting in a dumpster".

He has also proved ruthless about selling works that no longer take his fancy. And the sheer volume of his collection means that the competition for places at his new gallery, a former barracks in Chelsea, is strong.

Mr Saatchi bought Kevan's work Boys, consisting of 30 black and white paintings of dictators and war criminals, such as Hitler, Pol Pot and Radovan Karadzic, portrayed as children, when it was shown at the BA degree show at Central St Martins College of Art and Design in London, in the summer of 2004. She said: "I was pleased because it was a BA show and he normally only goes to MA shows. I'm hoping that it will be shown at the new gallery. I know he has had it framed, because I was asked to go and chose a frame with him, but I was too scared."

At 33, Kevans is a relatively late starter as a professional artist. Although she had wanted to paint since she was a child, she did not attend art college until she was 24 and then only part time. Her first solo exhibition opens at Studio 1.1, an artists collective gallery in east London, on Friday, and features a series of paintings of actresses and singers such as Charlotte Church and Jodie Foster, who first found success as child stars,

"Charles Saatchi's interest has been brilliant for my career, because its very difficult to get yourself established after leaving college," she said. "Lots of other collectors have expressed interest as a result. It can't help but get you noticed."

Her agent, Flora Fairbairn, said she hoped Boys would be shown at Chelsea next year. It was due to be part of the Triumph of Painting exhibition, postponed when the County Hall gallery closed last December in a dispute with its Japanese landlords. But, she said: "Saatchi is now buying so much, it is difficult to know what he is going to show or not.

"While it has been good for Annie, she is capable of success without his help. Many artists don't want to sell to him because if he sells you on quickly, it doesn't do a lot for your reputation.''

The opening of the new Saatchi Gallery in Chelsea is likely to reinforce Mr Saatchi's pre-eminence on the London art scene. Previews on his website show a series of large, open spaces, very different from the small rooms at County Hall, the former offices of the Greater London Council.

Ms Wright said: "People have suggested [Mr Saatchi] has lost his touch, but I think he is back in favour and people are happy to be bought by him. He has shown his ability to reinvent style and space and now believes he can do it anywhere."

Other protégés

* TOBY ZIEGLER

Sold a landscape painting to Saatchi for under £10,000 18 months ago and has since seen his work soar in value.

Ziegler, 33, trained at Central St Martins - the alma mater of many of the Young British Artist crowd - and now works from a studio in London.

Since being picked up by Saatchi, he has staged his first solo exhibition where his mixture of painting, sculpture and installation won plaudits from the critics.

* DAMIEN HIRST

One of the first and most famous of Saatchi's artists, He is worth an estimated £100m and is due to stage a new exhibition in London next year. His pickled shark was exhibited in the Sensation show at the Royal Academy in 1997. Saatchi bought it for £50,000 before selling it back to Hirst. An American collector bought it two years ago for £7m

* CONRAD SHAWCROSS

Son of royal biographer William Shawcross, the sculptor, 28, sold one of his mechanical machines to the collector for £26,000 two years ago.

Last year he sold five copies of a film he made of another of his machines for £45,000 and is now moving from a second floor studio above a cash and carry in east London to 5,000 sq feet of new space, partly as a result of Saatchi's patronage.

* TRACEY EMIN

Saatchi's taste was derided when he paid £150,000 for Emin's unmade, detritus-strewn bed six years ago. It is now worth £1M. Saatchi has said: "I was very slow to get the loopiness of Tracey's work. I'm a helpless fan now."