I have a 55lb lab mix, Scotia, along with my sugar glider, Lilly. My boyfriend and I already knew Scotia is afraid of Lilly, she used to be more curious and she does still like investigating but not getting too close anymore. When Lilly moves too quickly, Scotia jumps, when Lilly crabs, Scotia runs into the other room and hides.
The other night I had friends over and we had Scotia in her kennel and Lilly was out playing with my friends when she jumped to the floor and ran into Scotia's kennel. While I knew Scotia was afraid of Lilly, her mouth is still the same size as Lilly and my little girl could be gone in a snap. I ran to the cage, but Lilly stood inside of the kennel just staring Scotia down as she cowered in the corner of the cage in an attempt to stay as far away from Lilly as possible.

My dog was the same way when introduced to the new kitten, but they made peace over time.

I really wouldn't suggest letting them interact, though, because if the glider ever acts like prey the dog might decide to be the predator.

LOL.

I have a similar experience as well.

I have two gliders, Noodles and Tabu. Noodles always follows me around; sitting on my shoulder and staring at the world.

One day, he saw my boyfriend's cat. For who knows whatever reason, he suddenly glided down to the cat's back with his nails extended. The cat got the shocked of his life and ran away while Noodles jumped back onto my body with pride and confidence on his face.

Needless to say, I wasn't pleased with Noodles.