NK3 homeobox 2 also known asNKX3-2 is a humangene. It is a homolog ofbagpipe (bap) inDrosophila and therefore also known asBapx1 (bagpipe homeobox homolog1). Theprotein encoded by this gene is ahomeodomain containingtranscription factor.[5]
NKX3-2 plays a role in thedevelopment of the axial and limb skeleton.[6] Mutations disrupting the function of this gene are associated withspondylo-megaepiphyseal-metaphyseal dysplasia (SMMD).[7] Nkx3-2 in mice also regulatespatterning in the middle ear.[8] Two small bones in the middle ear, the malleus and incus, are homologous to the articular and quadrate, the bones of the proximal jaw joint in fish and other non-mammalian jawed vertebrates. NKX3-2 expression is required to pattern the articulated joint between these jaw bones, asknockdowns orknockouts of this gene result in the loss of the jaw joint in zebrafish,[9] chicken,[10] and amphibians.[11] Overexpression of this gene results in the development of ectopic mandibular cartilages in zebrafish[12] and amphibians.[13]
^"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.
^Yoshiura KI, Murray JC (October 1997). "Sequence and chromosomal assignment of human BAPX1, a bagpipe-related gene, to 4p16.1: a candidate gene for skeletal dysplasia".Genomics.45 (2):425–428.doi:10.1006/geno.1997.4926.PMID9344671.
^Tucker AS, Watson RP, Lettice LA, Yamada G, Hill RE (March 2004). "Bapx1 regulates patterning in the middle ear: altered regulatory role in the transition from the proximal jaw during vertebrate evolution".Development.131 (6):1235–1245.doi:10.1242/dev.01017.PMID14973294.S2CID447070.
^Wilson J, Tucker AS (February 2004). "Fgf and Bmp signals repress the expression of Bapx1 in the mandibular mesenchyme and control the position of the developing jaw joint".Developmental Biology.266 (1):138–150.doi:10.1016/j.ydbio.2003.10.012.PMID14729484.
^Lukas P, Olsson L (November 2018). "Bapx1 is required for jaw joint development in amphibians".Evolution & Development.20 (6):192–206.doi:10.1111/ede.12267.PMID30168254.S2CID52133937.
