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 [].
Bardet-Biedl syndrome is a member of genetic ciliopathies, but the link between cilia/centrosome deficits and metabolic abnormalities is not completely clear []. Bardet-Biedl syndrome (BBS) is a heterogeneous genetic disorder characterised by many features, including retinal degeneration, obesity, cognitive impairment, polydactyly, renal abnormalities, and hypogenitalism. BBS genes play an important role in maintaining leptin sensitivity in proopiomelanocortin neurons []. A relatively high incidence of BBS is found inthe mixed Arab populations of Kuwait and in Bedouin tribes throughout the Middle East, most likely due to the high rate of consaguinity in these populations and a founder effect.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 BBS2, which is required for leptin receptor signalling in the hypothalamus []. BBS2 and 4 are also required for the localisation of somatostatin receptor 3 and melanin-concentrating hormone receptor 1 into neuronal cilia [].
This entry represents the middle region of the Bardet-Biedl syndrome 2 protein. The BBSome (so-named after the association with Bardet-Biedl syndrome) is a complex of 8 subunits that lies at the base of the flagellar microtubule structure. The precise function of the all the individual components in cilia formation is unclear, however they function to promote loading of cargo to the ciliary axoneme []. The primary cilium, a slim microtubule-based organelle that projects from the surface of vertebrate cells has crucial roles in vertebrate development and human genetic diseases. Cilia are required for the response to developmental signals, and evidence is accumulating that the primary cilium is specialised for Hedgehog (Hh) signal transduction. Formation of cilia, in turn, is regulated by other signalling pathways, possibly including the planar cell polarity pathway. The connections between cilia and developmental signalling have begun to clarify the basis of human diseases associated with ciliary dysfunction [].BBS2 is one of the three Bardet-Biedl syndrome subunits that is required for leptin receptor signalling in the hypothalamus [], and BBS2 and 4 are also required for the localisation of somatostatin receptor 3 and melanin-concentrating hormone receptor 1 into neuronal cilia [].
This entry represents the N-terminal domain of the Bardet-Biedl syndrome 2 protein. The BBSome (so-named after the association with Bardet-Biedl syndrome) is a complex of 8 subunits that lies at the base of the flagellar microtubule structure. The precise function of the all the individual components in cilia formation is unclear, however they function to promote loading of cargo to the ciliary axoneme []. The primary cilium, a slim microtubule-based organelle that projects from the surface of vertebrate cells has crucial roles in vertebrate development and human genetic diseases. Cilia are required for the response to developmental signals, and evidence is accumulating that the primary cilium is specialised for Hedgehog (Hh) signal transduction. Formation of cilia, in turn, is regulated by other signalling pathways, possibly including the planar cell polarity pathway. The connections between cilia and developmental signalling have begun to clarify the basis of human diseases associated with ciliary dysfunction [].BBS2 is one of the three Bardet-Biedl syndrome subunits that is required for leptin receptor signalling in the hypothalamus [], and BBS2 and 4 are also required for the localisation of somatostatin receptor 3 and melanin-concentrating hormone receptor 1 into neuronal cilia [].
Bardet-Biedl syndrome (BBS) is a heterogeneous genetic disorder characterised by many features, including retinal degeneration, obesity, cognitive impairment, polydactyly, renal abnormalities, and hypogenitalism. The BBSome is a complex of 8 subunits that lies at the base of the flagellar microtubule structure. The precise function of the all the individual components in cilia formation is unclear, however they function to promote loading of cargo to the ciliary axoneme []. The primary cilium, a slim microtubule-based organelle that projects from the surface of vertebrate cells has crucial roles in vertebrate development and human genetic diseases. Cilia are required for the response to developmental signals, and evidence is accumulating that the primary cilium is specialised for Hedgehog (Hh) signal transduction. Formation of cilia, in turn, is regulated by other signalling pathways, possibly including the planar cell polarity pathway. The connections between cilia and developmental signalling have begun to clarify the basis of human diseases associated with ciliary dysfunction [].BBS2 is one of the three Bardet-Biedl syndrome subunits that is required for leptin receptor signalling in the hypothalamus [], and BBS2 and 4 are also required for the localisation of somatostatin receptor 3 and melanin-concentrating hormone receptor 1 into neuronal cilia [].
