KAT-TUN (カトゥーン, Katūn) is a Japanese boy band formed under Johnny & Associates (Johnny's) in 2001. The group's name was originally an acronym based on the first letter of each member's family name: Kazuya Kamenashi, Jin Akanishi, Junnosuke Taguchi, Koki Tanaka, Tatsuya Ueda, and Yuichi Nakamaru. Their debut on March 22, 2006 was marked by a tripartite release of a CD single, album and music DVD on their exclusive record label J-One Records. Since then, all of their single, album and music DVD releases have debuted at number one on the Oricon music and DVD charts.