AMBN
- Known as:
- AMBN
- Catalog number:
- 001510A
- Product Quantity:
- 250ul
- Category:
- -
- Supplier:
- ABM
- Gene target:
- AMBN
Related genes to: AMBN
- Gene:
- AMBN NIH gene
- Name:
- ameloblastin
- Previous symbol:
- -
- Synonyms:
- -
- Chromosome:
- 4q13.3
- Locus Type:
- gene with protein product
- Date approved:
- 1997-01-08
- Date modifiied:
- 2016-10-05
Related products to: AMBN
Related articles to: AMBN
- Ameloblastin (Ambn) is a tooth-specific multifunctional protein essential for enamel biomineralization and the formation of its prismatic microstructure. To examine the function of the evolutionarily conserved cell-binding Ambn amphipathic helix (AH) motif, we deleted the hydrophobic residues within the Ambn AH motif in genetically engineered mice. Enamel in the homozygous (Ambn) mutants had normal thickness but was hypo-mineralized and lacked prismatic structure. Micro-CT analysis further revealed that both the secretory and maturation stages of amelogenesis were delayed and proceeded slower than in the controls. Ameloblasts in the mutants were stunted and exhibited loss of cell polarity, as demonstrated by the mislocalization of Pard3, Claudin-1 and GM130 immunosignals. In the Ambn mutants, a loss of Ambn-ameloblast distal membrane interaction was observed, with nuclear localization of β-catenin and p-Smad2/3, and a decrease in RhoA immunolabeling intensity, suggesting that changes in known signaling pathways may connect Ambn-cell interactions to the establishment of cell polarity. Together, these findings support a model in which AH-dependent Ambn engagement at the distal ameloblast membrane contributes to secretory-stage polarity and prism patterning, with downstream consequences for enamel organization and maturation-stage mineral density. - Source: PubMed
Publication date: 2026/08/20
Visakan GayathriBapat Rucha ArunCai JingSuwandi Ethan TrevorJoester DerkKegulian Natalie CSarkisians EdwinAghazadeh MarziyehWebster SimonMoradian-Oldak Janet - remains have been found in Africa, Eurasia, and Southeast Asia, with a fossil record dating back to 2 million years, holding a significant place in human evolution. However, due to limited molecular evidence, its genetic characteristics, diversity, and potential connections to other archaic homonins and modern humans have long remained unresolved. To address these issues, a research team led by Qiaomei Fu from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, in collaboration with other archaeological institutions, successfully extracted ancient enamel proteins from six Middle Pleistocene teeth (~0.4 Ma) from the Zhoukoudian, Hexian, and Sunjiadong sites. Further in-depth paleoproteomic analyses revealed the following breakthroughs. First, a quantitative sex determination pipeline was established based on male-specific amelogenin, Y isoform (AMELY), confirming that five of these specimens are male and one is female. Second, two genetically specific amino acid variants in ameloblastin (AMBN) were identified in all specimens from three sites. One is a newly discovered variant, AMBN-253G, which has not been found in any other archaic or modern human populations. It represents a molecular marker specific to the East Asian Middle Pleistocene lineage, providing solid evidence that specimens from Zhoukoudian, Hexian, and Sunjiadong sites belonged to the same evolutionary lineage. The other variant, AMBN-273V, has previously been identified in Denisovans. However, genetic analysis in this study reveals that this variant may have been introduced into Denisovans through populations related to these Middle Pleistocene , and some of which subsequently contributed to certain modern human populations from Southeast Asia or Oceania. This study obtains lineage-specific molecular information from fossils for the first time, and reshapes our understanding of hominin evolution and the history of genetic admixture in East Asia. - Source: PubMed
Zou Zi-YiRao Hui-YunFu Qiao-Mei - Enamel, the outermost mineralized tissue of the tooth, is produced by specialized dental epithelial cells called ameloblasts. Unlike human enamel, which lacks regenerative capacity, the mouse incisor grows throughout life, driven by adult stem cells residing in the labial cervical loop (LaCl). To maintain tissue homeostasis, dental epithelial stem cells produce transit-amplifying cells (TACs) that commit to preameloblasts (PABs), migrate distally, and differentiate into enamel-forming ameloblasts. The full dental epithelial differentiation trajectory coexists within a single mouse incisor, making it an accessible model for studying adult tissue repair and regeneration. We have shown that the genome organizer SATB1 is enriched in PABs and is required for their differentiation into ameloblasts. Here, we investigated the injury response of PABs following mouse incisor tip trimming. Injured wild-type (wt) incisors exhibited an expanded PAB zone with intensive proliferation, reduced SATB1 in the ameloblast lineage, associated with a spatial delay in the deposition of the dentin/enamel matrix compared to uninjured controls. Trimming of Satb1 cKO mouse incisor failed to elicit this response, highlighting SATB1's role in PAB's response to injury. Compared with wt controls, injured wt incisors and both Satb1 cKO groups showed increased Ki67 immunoreactivity in LaCl mesenchymal and epithelial compartments, along with reduced Col1a1 expression in PAB microenvironment. In vitro, SATB1-transduced ameloblast lineage cells (ALCs) cultured on increasing concentrations of type I collagen exhibited reduced Ki67 but elevated Amelx/Ambn expression. There findings indicate that SATB1 is required for epithelial TACs to exit the cell cycle and transition toward PABs. Incisor tip injury delays PAB differentiation by stimulating LaCL mesenchymal proliferation and altering ECM remodeling within the PAB niche. - Source: PubMed
Publication date: 2026/08/14
Campbell AlexiaLin KevinNgu JakeAhlstrand Cierra RoseKohwi-Shigematsu TerumiZhang Yan - Autosomal dominant hypocalcified amelogenesis imperfecta (ADHCAI; OMIM#130900) is a hereditary enamel defect caused by truncation mutations in FAM83H, though the underlying pathogenic mechanisms remain incompletely understood. This study aimed to identify novel FAM83H mutations in a Chinese family with ADHCAI and to investigate their functional consequences on enamel formation. - Source: PubMed
Wang YueChen HongfeiLai JiyongHuang XueqingHuang Yanyu - Nephronectin (Npnt) is a multifunctional basement membrane protein containing EGF-like repeats and an RGD motif. While we previously reported that Npnt regulates dental epithelial stem cell proliferation via its EGF-like repeats, the specific role of its RGD motif in ameloblast differentiation remained to be elucidated. In this study, we investigated the domain-specific functions of Npnt and identified its functional receptors during tooth development. Using the dental epithelial cell line M3H1, we demonstrated that overexpression of full-length Npnt and an EGF-deleted mutant significantly induced the expression of the ameloblast differentiation marker ameloblastin (Ambn), whereas an RGD-deleted mutant failed to induce differentiation. Competitive inhibition assays using RGD peptides further confirmed that Npnt-mediated differentiation and cell adhesion are RGD-dependent. Analysis of single-cell RNA sequencing data from mouse incisors revealed that Integrin αV and β6 are highly enriched in differentiating ameloblasts. siRNA-mediated knockdown experiments confirmed that Integrin β6 is essential for Npnt-induced Ambn expression. Furthermore, we found that EGF signaling negatively regulates Npnt-mediated differentiation, suggesting a mechanism to prevent premature maturation. These findings suggest that Npnt orchestrates a functional switch in tooth development: it promotes ameloblast differentiation via the integrin αVß6 pathway through its RGD motif, a mechanism distinct from its EGF-mediated regulation of stemness. - Source: PubMed
Publication date: 2026/08/06
Mizuta KanjiChiba YutaTian TianShuai ShaoKozai NatsukiTakahashi IchiroFukumoto SatoshiYoshizaki Keigo