Brain-specific homeobox

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

  1. ^ "Entrez Gene: BSX brain-specific homeobox".
  2. ^ 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.
  3. ^ 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.
  4. ^ 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.
  5. ^ 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.
  6. ^ Schredelseker, Theresa; Driever, Wolfgang (1 July 2018). "Bsx controls pineal complex development". Development. 145 (13): dev163477. doi:10.1242/dev.163477. PMID 29945867.
  7. ^ 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.
  • v
  • t
  • e
(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) Cys2His2
(2.4) Cys6
(2.5) Alternating composition
(2.6) WRKY
(3) Helix-turn-helix domains
(3.1) Homeodomain
Antennapedia
ANTP class
protoHOX
Hox-like
metaHOX
NK-like
other
(3.2) Paired box
(3.3) Fork head / winged helix
(3.4) Heat shock factors
(3.5) Tryptophan clusters
(3.6) TEA domain
  • transcriptional enhancer factor
(4) β-Scaffold factors with minor groove contacts
(4.1) Rel homology region
(4.2) STAT
(4.3) p53-like
(4.4) MADS box
(4.6) TATA-binding proteins
(4.7) High-mobility group
(4.9) Grainyhead
(4.10) Cold-shock domain
(4.11) Runt
(0) Other transcription factors
(0.2) HMGI(Y)
(0.3) Pocket domain
(0.5) AP-2/EREBP-related factors
(0.6) Miscellaneous
see also transcription factor/coregulator deficiencies