Regulates ciliary localization of the BBSome complex. Together with the BBSome complex, controls SMO ciliary trafficking and contributes to the sonic hedgehog (SHH) pathway regulation. May play a role in neurite outgrowth. May have tumor suppressor function (By similarity). Self-associates. Interacts with BBS9; the interaction mediates the association of LZTL1 with the BBsome complex and regulates BBSome ciliary trafficking (By similarity). Belongs to the LZTFL1 family. Truncated N-terminus.