Bioinformatics Database

LMNA: lamin A/C

LMNA: lamin A/C
3D Protein Structure Viewer​
Cellular Process
Cap stage of tooth development
Gene Name
LMNA: lamin A/C
Gene ID
4000
General Description
The protein encoded by this gene is part of the nuclear lamina, a two-dimensional matrix of proteins located next to the inner nuclear membrane. The lamin family of proteins make up the matrix and are highly conserved in evolution. During mitosis, the lamina matrix is reversibly disassembled as the lamin proteins are phosphorylated. Lamin proteins are thought to be involved in nuclear stability, chromatin structure and gene expression.
Alternative titles; symbols
LAMIN A, LAMIN C; LMNC, PRELAMIN A, PROGERIN
Chromosome
Chromosome 1
Cytogenetic location
1q22
Function of the protein in oral and tooth development

The basement membranes of the developing tooth contain laminins. Salmivirta et al., (1997) studied differentail expression of laminin alpha chanins druing murine tooth development. The results showed that that both epithelial and mesenchymal cells produce laminin alpha chains. The mRNAs of three laminin alpha chains, alpha1, alpha2, and alpha4, were expressed in the tooth mesenchyme, whereas two, the alpha3 and alpha5 chain mRNAs, were found in epithelium (Salmivirta et al., 1997).

In a different study, Fukumoto et al., (2006) found that Lama5-null mice develop a small tooth germ with defective cusp formation and have reduced proliferation of dental epithelium. Cell polarity and formation of the monolayer of the inner dental epithelium are disturbed. The enamel knot, a signaling center for tooth germ development, is defective, and there is a significant reduction of Shh and Fgf4 expression in the dental epithelium. In the absence of laminin alpha5, the basement membrane in the inner dental epithelium becomes discontinuous (Fukumoto et al., 2006). The results indicate that that "laminin alpha5 is required for the proliferation and polarity of basal epithelial cells and suggest that the interaction between laminin-10/11-integrin alpha6beta4 and the phosphatidylinositol 3-kinase-Cdc42/Rac pathways play an important role in determining the size and shape of tooth germ" (Fukumoto et al., 2006).

As described by Yoshiba et al., (1998): "Tooth morphogenesis is regulated by epithelial-mesenchymal interactions mediated by the basement membrane (BM). Laminins are major glycoprotein components of the BMs, which are involved in several cellular activities. The expression and localization of the alpha3, beta3, and gamma2 laminin-5 subunits have been analyzed by in situ hybridization and immunohistochemistry during mouse molar development. Initially (E12), mRNAs of all subunits were detected in the entire dental epithelium and the corresponding proteins were located in the BM. During cap formation (E13-14), transcripts for the alpha3 and gamma2 subunits were localized in the outer dental epithelium (ODE), whereas the beta3 subunit mRNA was present in the inner dental epithelium (IDE)."

Dental and Oral Diseases
Protein Sequence
>NP_733821.1 lamin isoform A [Homo sapiens]
METPSQRRATRSGAQASSTPLSPTRITRLQEKEDLQELNDRLAVYIDRVRSLETENAGLRLRITESEEVV
SREVSGIKAAYEAELGDARKTLDSVAKERARLQLELSKVREEFKELKARNTKKEGDLIAAQARLKDLEAL
LNSKEAALSTALSEKRTLEGELHDLRGQVAKLEAALGEAKKQLQDEMLRRVDAENRLQTMKEELDFQKNI
YSEELRETKRRHETRLVEIDNGKQREFESRLADALQELRAQHEDQVEQYKKELEKTYSAKLDNARQSAER
NSNLVGAAHEELQQSRIRIDSLSAQLSQLQKQLAAKEAKLRDLEDSLARERDTSRRLLAEKEREMAEMRA
RMQQQLDEYQELLDIKLALDMEIHAYRKLLEGEEERLRLSPSPTSQRSRGRASSHSSQTQGGGSVTKKRK
LESTESRSSFSQHARTSGRVAVEEVDEEGKFVRLRNKSNEDQSMGNWQIKRQNGDDPLLTYRFPPKFTLK
AGQVVTIWAAGAGATHSPPTDLVWKAQNTWGCGNSLRTALINSTGEEVAMRKLVRSVTVVEDDEDEDGDD
LLHHHHGSHCSSSGDPAEYNLRSRTVLCGTCGQPADKASASGSGAQVGGPISSGSSASSVTVTRSYRSVG
GSGGGSFGDNLVTRSYLLGNSSPRTQSPQNCSIM
Mutations