This sounds like it might be Vermonia; four youth are transported from Earth to the Turtle Realm to defend it against the army of General Uro. They turn out to have been sent to Earth years before by Queen Frasinella before her world was destroyed, and each is bound to one of the Queen's ministers (in an animal form).
Jim is a skate freak and bass player in Union City but in the Turtle Realm he has been chosen by Suiran, the Winged Panther, to possess the power of wind and trees. Jim's fallen hard for Rainbow, a Potonawi Princess, and will fight against anyone or anything that threatens her and her people.
Doug is Jim's best friend and plays drums for their band Veracity. In the Turtle Realm he was the first to release his animal guardian Raitetsu, the Silver Tiger. Doug wears the sabertooth as a talisman and has Raitetsu's power to throw thunder.
Mel is the daughter of Union City's mayor and the lead vocalist for Veracity. She's a prisoner in Turtle Realm and unable to release Ruka, her guardian. Mel is being forced to use her powers of prophecy to fight for General Uro.
Naomi plays lead guitar for Veracity and is competing against Mel for the title of best skater in Union City. She leads the search for Mel in the Turtle Realm and draws upon the power of Suzaku, the Red Phoenix. Her animal guardian has given her the power of flight and fire.
Characters page on the official site