Parathyroid hormone-responsive B1 (PTHB1, also known as BBS9 in human) is part of the BBSome complex. The BBSome complex (contains BBS1, BBS2, BBS4, BBS5, BBS7, BBS8, BBS9 and BBIP10) is required for ciliogenesis but is dispensable for centriolar satellite function. This ciliogenic function is mediated in part by the Rab8 GDP/GTP exchange factor, which localises to the basal body and contacts the BBSome. Rab8(GTP) enters the primary cilium and promotes extension of the ciliary membrane. Firstly the BBSome associates with the ciliary membrane and binds to RAB3IP/Rabin8, the guanosyl exchange factor (GEF) for Rab8 and then the Rab8-GTP localizes to the cilium and promotes docking and fusion of carrier vesicles to the base of the ciliary membrane [].
This entry represents the N-terminal domain of the Bardet-Biedl syndrome 1 protein (BBS1).Bardet-Biedl syndrome is characterised by usually severe pigmentary retinopathy, early-onset obesity, polydactyly, hypogenitalism, renal malformation and mental retardation []. Bardet-Biedl syndrome proteins (BBS1, BBS2, BBS4, BBS5, BBS7, BBS8/TTC8, BBS9 and BBIP10) form the BBSome complex, which may function as a coat complex required for sorting of specific membrane proteins to the primary cilia []. The ciliary trafficking function of BBSome is regulated by LZTFL1 (Leucine-zipper transcription factor-like 1) [].
Tetratricopeptide repeat protein 8 (TTC8, also known as BBS8) is part of the BBSome complex (BBS1, BBS2, BBS4, BBS5, BBS7, BBS8/TTC8, BBS9 and BBIP10), which is thought to function as a coat complex required for sorting of specific membrane proteins to the primary cilia []. The ciliary trafficking function of the BBSome is regulated by LZTFL1 (Leucine-zipper transcription factor-like 1) [].Primary cilia are ubiquitous cellular appendages that provide important sensory and signalling functions and their dysfunction underlies numerous human genetic disorders. The proteins disrupted in the human ciliary disorder Bardet-Biedl syndrome (BBS) are required for the localisation of G protein-coupled receptors to primary cilia on central neurons. The alteration of signalling caused by mislocalisation of ciliary signalling proteins underlies the BBS phenotype []. BBS8 is one of the genes involved in BBS. A splice-site mutation in TTC8/BBS8 is also known to cause nonsyndromic retinitis pigmentosa (RP) [].
Bardet-Biedl syndrome is characterised by usually severe pigmentary retinopathy, early-onset obesity, polydactyly, hypogenitalism, renal malformation and mental retardation []. Bardet-Biedl syndrome proteins (BBS1, BBS2, BBS4, BBS5, BBS7, BBS8/TTC8, BBS9 and BBIP10) form the BBSome complex, which may function as a coat complex required for sorting of specific membrane proteins to the primary cilia []. The ciliary trafficking function of BBSome is regulated by LZTFL1 (Leucine-zipper transcription factor-like 1) [].Primary cilia are ubiquitous cellular appendages that provide important sensory and signalling functions and their dysfunction underlies numerous human genetic disorders. The proteins disrupted in the human ciliary disorder Bardet-Biedl syndrome (BBS) are required for the localisation of G protein-coupled receptors to primary cilia on central neurons. The alteration of signalling caused by mislocalisation of ciliary signalling proteins underlies the BBS phenotype []. Of the 12 known BBS genes, BBS1 is the most commonly mutated [].This entry represents BBS1.
Bardet-Biedl syndrome is characterised by usually severe pigmentary retinopathy, early-onset obesity, polydactyly, hypogenitalism, renal malformation and mental retardation []. Bardet-Biedl syndrome proteins (BBS1, BBS2, BBS4, BBS5, BBS7, BBS8/TTC8, BBS9 and BBIP10) form the BBSome complex, which may function as a coat complex required for sorting of specific membrane proteins to the primary cilia []. The ciliary trafficking function of BBSome is regulated by LZTFL1 (Leucine-zipper transcription factor-like 1) [].Primary cilia are ubiquitous cellular appendages that provide important sensory and signalling functions and their dysfunction underlies numerous human genetic disorders. The proteins disrupted in the human ciliary disorder Bardet-Biedl syndrome (BBS) are required for the localisation of G protein-coupled receptors to primary cilia on central neurons. The alteration of signalling caused by mislocalisation of ciliary signalling proteins underlies the BBS phenotype []. Of the 12 known BBS genes, BBS1 is the most commonly mutated [].This entry represents BBS4. It may participate in triallelic inheritance with BBS2 and BBS1 [].
