For the first time in almost 50 years, Versace will no longer be designed by a Versace.

Three decades after she started working for the company – and 27 years after she stepped into the role of creative director after the murder of her brother, Gianni – the designer Donatella Versace has announced she is to step down from her role at the Italian brand from the end of March.

“It has been the greatest honour of my life to carry on my brother Gianni’s legacy,” she said in a statement on Thursday morning. “He was the true genius, but I hope I have some of his spirit and tenacity.”

From April, Dario Vitale, 41, a former image director at Miu Miu, the edgier sister brand to Prada, will be Versace’s creative director. Versace will not leave the company – instead she will become chief brand ambassador, looking after (among other roles) philanthropy and red carpet dressing. Of the new role, Donatella said: “I will remain Versace’s most passionate supporter. Versace is in my DNA and always in my heart.”

Versace, the youngest and only daughter of a dressmaker in Reggio Calabria, was born in 1955, a decade after her eldest brother, Gianni. Though she left home to study in Florence, along with Santo, the middle brother who ran the business side, she was very much involved in the family business as a supporter and a muse to her brother. By 1989, aged 34, she began working at Atelier Versace, and by 1993 had sole creative responsibility for Versus, Versace’s cheaper diffusion line.

It was after the murder of Gianni in 1997 – the 50-year-old designer was shot outside his home in Miami Beach – that Donatella, unexpectedly, was propelled into the top job. Despite having no formal fashion training, she inherited a $807m (£623m) business and 130 shops worldwide. Talking about that time in the Guardian in 2017, she said: “For the first five years, I was lost … I made a lot of mistakes. I would tell myself … don’t try to be Gianni!”

At its height, under Gianni, Versace specialised in an aesthetic, synonymous with “flashion” and vulgarity and starry front rows. But with a knack for telling a story through the clothes themselves, Donatella became just as entwined with the look.

One of the few brands with a designer who is as much a visual ambassador of the clothes as the customer – not to mention one of the few women in a top job at a fashion house – Versace not only wore the brand, but became it. Instantly recognisable, in 2015 she even briefly appeared as the face of Givenchy.

Although Versace’s status in popular culture rose on Gianni’s watch – he designed Liz Hurley’s safety-pin dress and choreographed the famous 1991 show in which the supermodels Naomi Campbell, Cindy Crawford and Linda Evangelista lip-synche to George Michael’s Freedom on the catwalk – it was consolidated by Donatella, who went on to work closely with Madonna and design, among other things, interiors, hotels and Jennifer Lopez’s plunging “jungle” dress worn to the Grammy’s in 2000. The outfit spawned so many search queries that Google created what is now Google Images.

Despite a few dips – Donatella has been vocal about her addictions and the company almost filed for bankruptcy in the early 2000s – she grew into the recognisable figurehead of the company, a champion for LGBTQ+ rights and a beloved character within the fashion industry.

The change in leadership marks not only a historic transition for the brand, but a financial one too. In the statement on Thursday, John D Idol, the chief executive officer of Capri Holdings which owns Versace as well as Michael Kors and Jimmy Choo, called the decision “part of a thoughtful succession plan”.

It is also thought that the Prada group, which owns Miu Miu, wants to buy Versace and has an exclusive bidding window on the brand – and that Vitale will provide a new wave of energy. During his tenure at Miu Miu, the brand recorded a 58% increase in revenue, to €649m (£544m). Sales were up 93% last year.

Vitale is not a well known name in fashion. But he had been rumoured to be a contender for roles at Bottega Veneta and Gucci. In his own statement, thanking Donatella, he described his new position as “a privilege”.