Protein encoded by the BSX gene
Brain-specific homeobox is a protein that in humans is encoded by the BSX gene .[ 1]
Structure and expression pattern
Bsx is an evolutionarily highly-conserved homeodomain-containing transcription factor that belongs to the ANTP-class.[ 2] In mouse it has been shown to be expressed in the telencephalic septum , pineal gland , the mammillary bodies and arcuate nucleus .[ 3]
Function in the hypothalamus
In the hypothalamic arcuate nucleus , Bsx has been demonstrated to be necessary for normal expression levels of the two orexigenic neuropeptides Agouti-related peptide and Neuropeptide Y .[ 4]
Function in the pineal gland
In the pineal gland of the clawed frog Xenopus , Bsx is expressed following the circadian rhythm and controls photoreceptor cell differentiation .[ 5] In zebrafish Bsx is required for normal development of all cell types within the pineal gland , including melatonin -releasing pinealocytes, photoreceptor cells and leftwards migrating parapineal cells,[ 6] which in zebrafish are crucial for the establishment of brain asymmetry .[ 7]
References
^ "Entrez Gene: BSX brain-specific homeobox" .
^ Ferrier, David E. K. (14 April 2016). "Evolution of Homeobox Gene Clusters in Animals: The Giga-Cluster and Primary vs. Secondary Clustering" . Frontiers in Ecology and Evolution . 4 . doi :10.3389/fevo.2016.00036 . hdl :10023/8685 .
^ Cremona, M; Colombo, E; Andreazzoli, M; Cossu, G; Broccoli, V (January 2004). "Bsx, an evolutionary conserved Brain Specific homeoboX gene expressed in the septum, epiphysis, mammillary bodies and arcuate nucleus". Gene Expression Patterns . 4 (1): 47– 51. doi :10.1016/S1567-133X(03)00151-0 . PMID 14678827 .
^ Sakkou, M; Wiedmer, P; Anlag, K; Hamm, A; Seuntjens, E; Ettwiller, L; Tschöp, MH; Treier, M (June 2007). "A role for brain-specific homeobox factor Bsx in the control of hyperphagia and locomotory behavior" . Cell Metabolism . 5 (6): 450– 63. doi :10.1016/j.cmet.2007.05.007 . PMID 17550780 .
^ D'Autilia, S.; Broccoli, V.; Barsacchi, G.; Andreazzoli, M. (22 March 2010). "Xenopus Bsx links daily cell cycle rhythms and pineal photoreceptor fate" . Proceedings of the National Academy of Sciences . 107 (14): 6352– 6357. Bibcode :2010PNAS..107.6352D . doi :10.1073/pnas.1000854107 . PMC 2852004 . PMID 20308548 .
^ Schredelseker, Theresa; Driever, Wolfgang (1 July 2018). "Bsx controls pineal complex development" . Development . 145 (13): dev163477. doi :10.1242/dev.163477 . PMID 29945867 .
^ Duboc, Véronique; Dufourcq, Pascale; Blader, Patrick; Roussigné, Myriam (23 November 2015). "Asymmetry of the Brain: Development and Implications". Annual Review of Genetics . 49 (1): 647– 672. doi :10.1146/annurev-genet-112414-055322 . PMID 26442849 .
(1) Basic domains
(1.1) Basic leucine zipper (bZIP )(1.2) Basic helix-loop-helix (bHLH )
Group A Group B Group C bHLH-PAS Group D Group E Group F bHLH-COE
(1.3) bHLH-ZIP (1.4) NF-1 (1.5) RF-X (1.6) Basic helix-span-helix (bHSH)
(2) Zinc finger DNA-binding domains
(2.1) Nuclear receptor (Cys4 )
subfamily 1 subfamily 2 subfamily 3 subfamily 4 subfamily 5 subfamily 6 subfamily 0
(2.2) Other Cys4 (2.3) Cys2 His2 (2.4) Cys6 (2.5) Alternating composition (2.6) WRKY
(4) β-Scaffold factors with minor groove contacts
(0) Other transcription factors