KAT-TUN (カトゥーン, Katūn?) is a Japanese boy band formed by Johnny & Associates (Johnny's) in 2001. The group's name is an acronym based on the first letter of each member's family name until the departure of Jin Akanishi in 2010. As of 2010, KAT-TUN stands for Kazuya KAmenashi, 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.