Ameloblastin

Protein-coding gene in the species Homo sapiens
AMBN
Identifiers
AliasesAMBN, AI1F, Sheathlin, ameloblastin
External IDsOMIM: 601259; MGI: 104655; HomoloGene: 7625; GeneCards: AMBN; OMA:AMBN - orthologs
Gene location (Human)
Chromosome 4 (human)
Chr.Chromosome 4 (human)[1]
Chromosome 4 (human)
Genomic location for AMBN
Genomic location for AMBN
Band4q13.3Start70,592,256 bp[1]
End70,607,288 bp[1]
Gene location (Mouse)
Chromosome 5 (mouse)
Chr.Chromosome 5 (mouse)[2]
Chromosome 5 (mouse)
Genomic location for AMBN
Genomic location for AMBN
Band5 E1|5 43.63 cMStart88,603,850 bp[2]
End88,616,390 bp[2]
RNA expression pattern
Bgee
HumanMouse (ortholog)
Top expressed in
  • testicle

  • putamen

  • caudate nucleus

  • gonad

  • nucleus accumbens

  • islet of Langerhans

  • Epithelium of choroid plexus

  • ventricular zone

  • prefrontal cortex

  • mesencephalon
Top expressed in
  • molar

  • membranous bone

  • maxilla

  • sexually immature organism

  • mandible

  • Inner enamel epithelium

  • fossa

  • lumbar subsegment of spinal cord

  • incisor

  • dermis
More reference expression data
BioGPS
n/a
Gene ontology
Molecular function
  • structural constituent of tooth enamel
  • growth factor activity
  • protein binding
Cellular component
  • extracellular region
  • endoplasmic reticulum lumen
Biological process
  • odontogenesis of dentin-containing tooth
  • biomineral tissue development
  • cell adhesion
  • cell population proliferation
  • post-translational protein modification
  • regulation of signaling receptor activity
  • regulation of cell population proliferation
  • signal transduction
Sources:Amigo / QuickGO
Orthologs
SpeciesHumanMouse
Entrez

258

11698

Ensembl

ENSG00000178522

ENSMUSG00000029288

UniProt

Q9NP70

O55189

RefSeq (mRNA)

NM_016519

NM_009664
NM_001303431

RefSeq (protein)

NP_057603

NP_001290360
NP_033794

Location (UCSC)Chr 4: 70.59 – 70.61 MbChr 5: 88.6 – 88.62 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

Ameloblastin (abbreviated AMBN and also known as sheathlin or amelin) is an enamel matrix protein that in humans is encoded by the AMBN gene.[5]

Function

Ameloblastin is a specific protein found in tooth enamel. Although less than 5% of enamel consists of protein, ameloblastins constitute 5–10% of all enamel protein, making it the second most abundant enamel matrix protein.[6] This protein is formed by ameloblasts during the early secretory to late maturation stages of amelogenesis. Although not completely understood, the function of ameloblastins is believed to be in controlling the elongation of enamel crystals and generally directing enamel mineralization during tooth development. Ameloblastin helps in the growth of a crystalline enameloid layer consisting of randomly oriented short enamel crystals.[7] Ameloblastin cleavage products are found in the sheath space between rod and interrod enamel, while intact ameloblastin accumulates on the enamel rods. This difference in localization is thought to maintain the boundary between rod and interrod enamel.[6][8]

Ameloblastin is generally implicated in enamel development, but may also have a role in root development.[6] Other possible actions include bone remodeling and repair, although this function has yet to be definitively proven.[6]

Other significant proteins in enamel are amelogenins, enamelins, and tuftelins.

Clinical significance

Mutations in AMBN cause amelogenesis imperfecta, a disease characterized by abnormal enamel formation resulting in discolored, pitted, or spotted enamel.[9] These mutations are rare, and follow an autosomal recessive pattern of inheritance.[6]

References

  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000178522 – Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000029288 – Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ "Entrez Gene: Ameloblastin (enamel matrix protein)".
  6. ^ a b c d e Hu JC, Chun YH, Al Hazzazzi T, Simmer JP (2007). "Enamel formation and amelogenesis imperfecta". Cells Tissues Organs. 186 (1): 78–85. doi:10.1159/000102683. PMID 17627121. S2CID 28367304.
  7. ^ Pandya M, Diekwisch TG (December 2021). "Amelogenesis: Transformation of a protein-mineral matrix into tooth enamel". Journal of Structural Biology. 213 (4): 107809. doi:10.1016/j.jsb.2021.107809. PMC 8665087. PMID 34748943.
  8. ^ Bartlett JD (September 2013). "Dental enamel development: proteinases and their enamel matrix substrates". ISRN Dentistry. 2013: 684607. doi:10.1155/2013/684607. PMC 3789414. PMID 24159389.
  9. ^ Poulter JA, Murillo G, Brookes SJ, Smith CE, Parry DA, Silva S, et al. (October 2014). "Deletion of ameloblastin exon 6 is associated with amelogenesis imperfecta". Human Molecular Genetics. 23 (20): 5317–5324. doi:10.1093/hmg/ddu247. PMC 4168819. PMID 24858907.


Further reading

  • Bartlett JD, Simmer JP (1999). "Proteinases in developing dental enamel". Critical Reviews in Oral Biology and Medicine. 10 (4): 425–441. doi:10.1177/10454411990100040101. PMID 10634581.
  • MacDougall M, DuPont BR, Simmons D, Reus B, Krebsbach P, Kärrman C, et al. (April 1997). "Ameloblastin gene (AMBN) maps within the critical region for autosomal dominant amelogenesis imperfecta at chromosome 4q21". Genomics. 41 (1): 115–118. doi:10.1006/geno.1997.4643. PMID 9126491.
  • Kuroda S, Wazen R, Sellin K, Tanaka E, Moffatt P, Nanci A (July 2011). "Ameloblastin is not implicated in bone remodelling and repair". European Cells & Materials. 22: 56–66, discussion 66–7. doi:10.22203/eCM.v022a05. PMID 21761392.
  • Perdigão PF, Carvalho VM, DE Marco L, Gomez RS (August 2009). "Mutation of ameloblastin gene in calcifying epithelial odontogenic tumor". Anticancer Research. 29 (8): 3065–3067. PMID 19661317.
  • Tamburstuen MV, Reseland JE, Spahr A, Brookes SJ, Kvalheim G, Slaby I, et al. (February 2011). "Ameloblastin expression and putative autoregulation in mesenchymal cells suggest a role in early bone formation and repair". Bone. 48 (2): 406–413. doi:10.1016/j.bone.2010.09.007. PMC 4469498. PMID 20854943.
  • Toyosawa S, Fujiwara T, Ooshima T, Shintani S, Sato A, Ogawa Y, et al. (October 2000). "Cloning and characterization of the human ameloblastin gene". Gene. 256 (1–2): 1–11. doi:10.1016/s0378-1119(00)00379-6. PMID 11054529.
  • Patir A, Seymen F, Yildirim M, Deeley K, Cooper ME, Marazita ML, Vieira AR (2008). "Enamel formation genes are associated with high caries experience in Turkish children". Caries Research. 42 (5): 394–400. doi:10.1159/000154785. PMC 2820320. PMID 18781068.
  • Lee SK, Krebsbach PH, Matsuki Y, Nanci A, Yamada KM, Yamada Y (December 1996). "Ameloblastin expression in rat incisors and human tooth germs". The International Journal of Developmental Biology. 40 (6): 1141–1150. PMID 9032019.
  • Niu CH, Li TJ (November 2006). "[Mutation and polymorphism of the ameloblastin gene in ameloblastomas]". Zhonghua Kou Qiang Yi Xue Za Zhi = Zhonghua Kouqiang Yixue Zazhi = Chinese Journal of Stomatology (in Chinese). 41 (11): 678–681. PMID 17331365.

External links