Cavendish lead-out man Pate signs for Sky
The deal for experienced American Pate, 32, comes amid speculation that top sprinter Cavendish will sign for Sky for next season.
Team Sky said in a statement: "Pate immediately settled in [at HTC] and became one of Mark Cavendish’s main lead-out men as the Manxman became the first British rider ever to win the green jersey at the Tour de France."
Pate won the world U23 time trial championship in 2001 but did not arrive in Europe until 2006, with TIAA-CREF.
He became one of the renamed Garmin team's key domestiques and helped them to a team time trial success at the 2008 edition of the Giro d'Italia while securing individual podiums on stages on that year's Tour de France and the following season's Giro. He moved to HTC in 2011.
"I was fortunate to have a number of offers from teams for next season," said Pate of his move to Sky.
"After riding with HTC-Highroad, I wanted to stay at the highest level in cycling and be part of the most professional team in the peloton. That is why I have chosen Team Sky and I am delighted to be joining one of the best-structured teams ever in cycling.
"Team Sky has a fantastic back room staff, some highly talented riders and a shared motivation to be the best. I know it’s a team that I am going to do well with and I am very proud to be joining this ambitious and exciting project.
"For the team my work as a domestique will remain my main focus and on a personal level I will be looking to target the World Championship TTT in 2012."
Team Sky principal Dave Brailsford said: "Danny is a hugely experienced rider with a fantastic pedigree. As well as being one of the peloton’s strongest riders he is also a world-class time triallist and has shown again this year that he is one of the sport’s most talented riders.
"His experience was also a major attraction for us and we will be looking to him to impart some of that on the younger guys in the team."