The 22-year-old centre has put pen to paper on a new deal that will see him play a pivotal role in the club's progress until at least the end of May 2015.
Currently a contracted member of the Scotland 7s squad, Horne, like back-row forward James Eddie, will complete his commitments in the abbreviated game before rejoining the Warriors set-up on a full-time basis in the summer.
With a leg of the HSBC Sevens World Series coming to Scotstoun Stadium in May, the Fifer is in line for an early sample of on-field action at the ground that will be the Warriors' playing home from next season.
Prior to joining up with the Scotland 7s earlier this campaign, Horne was in fine form for Sean Lineen's men, underlining his attacking threat with a brilliantly constructed match-winning try in the historic RaboDirect PRO12 victory away to Leinster.
The former Howe of Fife and West of Scotland player told www.glasgowwarriors.org: "I'm thrilled to have signed a new contract with the Warriors. All the signs are that it's going to be an exciting place to be over the next few years, and I'm delighted to have the opportunity to be part of that.
"I'm really enjoying my time with Scotland 7s, and with six tournaments to play, including the one in Glasgow, there's a huge amount to look forward to on that front over the rest of the season.
"I'll be giving my all to win selection for those tournaments and help the team achieve success, before coming back to the Warriors and doing my bit to help the club build on the positive signs we've seen both on and off the pitch this season."
Head coach Lineen commented: "Identifying and tying down our best young players is key to the progress everyone at Glasgow Warriors strongly believes is possible over this and the coming seasons.
"I've been a big fan of Pete for quite some time, and he's really come on as a player since he joined us from the National Academy in 2009. He's got the full range of skills for the modern centre - great hands, a confident kicking game, and an excellent step.
"Allied to those gifts, he's one of the bravest guys around and he'll run himself into the ground for the team. Playing with Scotland 7s has been fantastic for his game, especially his decision-making under pressure, and I'm really looking forward to working with him to ensure he fulfils his undoubted potential."
Horne is the tenth Warriors player to commit his long-term future to the club in recent months, joining Chris Cusiter, Eddie, Chris Fusaro, Ryan Grant, Rob Harley, Stuart Hogg, Ruaridh Jackson, Duncan Weir and Ryan Wilson.
Glasgow, who can still qualify for the Amlin Challenge Cup quarter-finals, finish their Heineken Cup Pool 3 campaign with a game against Bath Rugby at the Recreation Ground on Saturday (kick-off 1.30pm).
They then face Scarlets at Firhill on Thursday 9 February (kick-off 7.05pm) in a clash that's crucial to their bid to remain in the RaboDirect PRO12 play-off places.
Tickets for the Scarlets match are available via www.glasgowwarriors.org, by calling 0844 800 3490 and in person at the Gordon Street and Sauchiehall Street branches of Greaves Sports, our official retail partners.
Guinness PRO12
Suite 208, Alexandra House,
The Sweepstakes
Ballsbridge, Dublin 4, Ireland