ABSTRACT
Both the major and minor salivary glands are the sources of saliva, a fluid vital for the maintenance of a healthy oral cavity. Here, the expression profiles of human submandibular (SMG) and labial glands (LG) were compared by RT-PCR analysis of laser microdissected mucous and serous cells, respectively. The focus was on trefoil factor family (TFF) genes, but also other genes encoding secretory proteins (mucins, lysozyme, amylase, statherin, and histatins) or aquaporin 5 were included. Immunofluorescence studies concerning TFF1-3, FCGBP, amylase, and lysozyme are also presented. It was shown that LGs clearly contain serous cells and that these cells differ in their expression profiles from serous SMG cells. Furthermore, all three TFF peptides, together with MUC5B, MUC7, MUC19, and FCGBP, were clearly detectable in mucous acini of both LGs and SMGs. In contrast, lysozyme was differentially expressed in LGs and SMGs. It can be expected that labial saliva may play a particularly important role for protecting the teeth.
Subject(s)
Salivary Glands/metabolism , Salivary Proteins and Peptides/metabolism , Amylases/genetics , Amylases/metabolism , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Gene Expression Regulation , Humans , Lasers , Microdissection , Mucin-5B/genetics , Mucin-5B/metabolism , Mucins/genetics , Mucins/metabolism , Muramidase/genetics , Muramidase/metabolism , Salivary Glands, Minor/metabolism , Salivary Proteins and Peptides/genetics , Submandibular Gland/metabolism , Trefoil Factor-1 , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolismABSTRACT
Craniofrontonasal syndrome (CFNS) is an X-linked craniofacial disorder with an unusual manifestation pattern, in which affected females show multiple skeletal malformations, whereas the genetic defect causes no or only mild abnormalities in male carriers. Recently, we have mapped a gene for CFNS in the pericentromeric region of the X chromosome that contains the EFNB1 gene, which encodes the ephrin-B1 ligand for Eph receptors. Since Efnb1 mutant mice display a spectrum of malformations and an unusual inheritance reminiscent of CFNS, we analyzed the EFNB1 gene in three families with CFNS. In one family, a deletion of exons 2-5 was identified in an obligate carrier male, his mildly affected brother, and in the affected females. In the two other families, missense mutations in EFNB1 were detected that lead to amino acid exchanges P54L and T111I. Both mutations are located in multimerization and receptor-interaction motifs found within the ephrin-B1 extracellular domain. In all cases, mutations were found consistently in obligate male carriers, clinically affected males, and affected heterozygous females. We conclude that mutations in EFNB1 cause CFNS.