In the chick embryo, Sox21 promotes neuronal cellular differentiation by counteracting the activity of Sox1, Sox2, and Sox3, which maintain neural cells in an undifferentiated state.[7]
SOX21 knockout mice display hair loss beginning from postnatal day 11. New hair regrowth was initiated a few days later but was followed by renewed hair loss. Sox21 is also expressed in the hair shaft cuticle in humans and consequently variants of the Sox21 gene could be responsible for some hair loss conditions in humans.
[8]
^"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.
^Malas S, Duthie S, Deloukas P, Episkopou V (Sep 1999). "The isolation and high-resolution chromosomal mapping of human SOX14 and SOX21; two members of the SOX gene family related to SOX1, SOX2, and SOX3". Mammalian Genome. 10 (9): 934–7. doi:10.1007/s003359901118. PMID10441749. S2CID27862567.
Stevanović M, Lovell-Badge R, Collignon J, Goodfellow PN (Dec 1993). "SOX3 is an X-linked gene related to SRY". Human Molecular Genetics. 2 (12): 2013–8. doi:10.1093/hmg/2.12.2013. PMID8111369.
1gt0: CRYSTAL STRUCTURE OF A POU/HMG/DNA TERNARY COMPLEX
1o4x: TERNARY COMPLEX OF THE DNA BINDING DOMAINS OF THE OCT1 AND SOX2 TRANSCRIPTION FACTORS WITH A 19MER OLIGONUCLEOTIDE FROM THE HOXB1 REGULATORY ELEMENT