The Dante Stakes is a Group Two race over one mile, two furlongs that is generally seen as a major trial for the Epsom Derby in June.
Unbeaten in two outings, Hurricane Lane, who is the son of Frankel, comfortably got the better of much more experienced rivals at Newbury in April.
That display persuaded Appleby that it was worth stepping up in class with a colt - who was recently added to the Cazoo Derby field.
Gear Up is a general 33-1 chance for the Cazoo Derby, after he ended his juvenile campaign with a Group One victory in the Criterium de Saint-Cloud in October.
"The Dante is usually a very good trial for the Derby, and Hurricane Lane is worthy of having a crack at it," said Appleby.
Johnston also has had the Group Two Dante in mind as a starting point for Gear Up for some time.
"Obviously we haven't run him yet, but the plan is to go to the Dante and that still is the plan at the moment," he said.
"Everything has gone fine."
Appleby has plenty of depth to his three-year-old squad this season. He is set to be doubly represented in the 2000 Guineas by Master Of The Seas and One Ruler, and supplied the second and third in the Sandown Classic Trial in Adayar and Yibir.
"On all evidence so far, Adayar is going to appreciate stepping up in trip, which could be in the Lingfield Derby Trial," he told www.godolphin.com.
"But he doesn't want the ground too quick, so he has the Dante at York as alternative.
"I was very pleased with Yibir's seasonal debut. He is only going to get better when he gets to a mile and a half, which he will get in the Chester Vase, his next race.
"I also plan to send Wirko (Epsom's Blue Riband Trial winner) to Chester for the Dee Stakes. It will be more good experience for him. The Epsom race was a 'win and you're in' for the Derby - we already know he can handle the track.
La Barrosa, who chased home Master Of The Seas in the Craven, will head for the French Guineas.
Appleby added: "He has done well since the Craven, and it is best to put a line though his previous run in France in the Criterium International at Saint-Cloud (when fifth). He did not like the heavy ground.
"We are very encouraged by the signs so far and excited with what we have. We are always looking for the next three-year-old champion, and we are very happy the way this group are developing."