| Down syndrome cell adhesion molecule, chordates | |
|---|---|
| Identifiers | |
| Symbol | DSCAM_chordates |
| InterPro | IPR033027 |
DSCAM and Dscam are both abbreviations for Down syndrome cell adhesion molecule.[5] In humans, DSCAM refers to a gene that encodes one of several protein isoforms.[6]
Down syndrome (DS), caused by trisomy 21, is the most common birth defect associated with intellectual disability. DSCAM plays a crucial role in the development of DS: it is expressed in the developing nervous system, with the highest level of expression occurring in the fetal brain. When over-expressed in the developing fetal central nervous system, it leads to Down syndrome.
A homologue of the Dscam protein in Drosophila melanogaster has 38,016 isoforms[7] arising from four variable exon clusters (12, 48, 33 and 2 alternatives, respectively).[5] By comparison, the entire Drosophila melanogaster genome only has 15,016 genes. The diversity of isoforms from alternative splicing of the Dscam1 gene in D. melanogaster allows every neuron in the fly to display a unique set of Dscam proteins on its cell surface. Dscam interaction stimulates neuronal self-avoidance mechanisms that are essential for normal neural circuit development.[8]
- ^ a b c GRCh38: Ensembl release 89: ENSG00000171587 – Ensembl, May 2017
- ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000050272 – Ensembl, May 2017
- ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- ^ a b Schmucker D, Clemens JC, Shu H, Worby CA, Xiao J, Muda M, Dixon JE, Zipursky SL (June 2000). "Drosophila Dscam is an axon guidance receptor exhibiting extraordinary molecular diversity". Cell. 101 (6): 671–84. doi:10.1016/S0092-8674(00)80878-8. PMID 10892653.
- ^ Alves-Sampaio, Alexandra; José Antonio Troca-Marín; María Luz Montesinos (6 October 2010). "NMDA-Mediated Regulation of DSCAM Dendritic Local Translation Is Lost in a Mouse Model of Down's Syndrome". The Journal of Neuroscience. 30 (40): 13537–13548. doi:10.1523/JNEUROSCI.3457-10.2010. PMC 6634725. PMID 20926679.
- ^ Neves, G.; Zucker J; Daly M; Chess A. (February 2004). "Stochastic yet biased expression of multiple Dscam splice variants by individual cells". Nature Genetics. 36 (3): 240–246. doi:10.1038/ng1299. PMID 14758360.
- ^ Hattori D, Millard SS, Wojtowicz WM, Zipursky SL (2008). "Dscam-mediated cell recognition regulates neural circuit formation". Annu. Rev. Cell Dev. Biol. 24 (1): 597–620. doi:10.1146/annurev.cellbio.24.110707.175250. PMC 2711549. PMID 18837673.