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. Self-associates. Interacts with BBS9; the interaction mediates the association of LZTL1 with the BBsome complex and regulates BBSome ciliary trafficking. Expressed in prostate, ovary, stomach, pancreas, esophagus, breast, liver, bladder, kidney, thyroid, colon and lung (at protein level). Down-regulated in multiple primary tumors (at protein level). Detected in testis, heart, skeletal muscle, thymus, spleen, small intestine, and peripheral blood leukocytes. Expressed in brain, lung, liver, and kidney. The disease is caused by variants affecting the gene represented in this entry. Patients carrying LZTFL1 mutations manifest mesoaxial polydactyly, a clinical feature very uncommon for Bardet-Biedl syndrome (PubMed:22510444 and PubMed:23692385). Some patients manifest situs inversus (PubMed:22510444). Belongs to the LZTFL1 family.