ABSTRACT
BACKGROUND: The inhibitor of DNA binding 4 (ID4) protein regulates osteogenic and adipogenic cell fate and lack of lD4 gene expression decreased osteoblast differentiation. Variant in the ID4 gene polymorphism has not been reported with osteoporosis. OBJECTIVE: To identify whether ID4 can be a marker gene for osteoporosis in Thai menopausal women. MATERIAL AND METHOD: The 3 'UTR of lD4 (rs3798339) single nucleotide polymorphism was examined bypolymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP), together with lumbar spine bone mineral density (BAMD) in 160 Thai menopausal women. RESULTS: Lumbar spine 3 (L3) had a significantly lower BMD score in women with the TT genotype, compared with the CT+CC genotypes (p = 0.037). This disappeared after the adjustment of various factors. CONCLUSION: The polymorphism at 3'UTR of lD4 gene can alter ID4 mRNA stability, and may be linked to the function of proteins. However, this needs confirmation in larger populations. The present study is useful as an initial investigation into ID4 gene polymorphism in osteoporosis.
Subject(s)
3' Untranslated Regions/genetics , Inhibitor of Differentiation Proteins/genetics , Osteoporosis, Postmenopausal/genetics , Polymorphism, Genetic , Adult , Aged , Asian People , Bone Density/physiology , Female , Genotype , Humans , Lumbar Vertebrae/physiology , Middle Aged , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Polymorphism, Single Nucleotide , ThailandABSTRACT
The sense of taste plays an important role in the evaluation of the nutrient composition of consumed food. Bitter taste in particular is believed to serve a warning function against the ingestion of poisonous substances. In the past years enormous progress was made in the characterization of bitter taste receptors, including their gene expression patterns, pharmacological features and presumed physiological roles in gustatory as well as in non-gustatory tissues. However, due to a lack in TAS2R-specifc antibodies the localization of receptor proteins within gustatory tissues has never been analyzed. In the present study we have screened a panel of commercially available antisera raised against human bitter taste receptors by immunocytochemical experiments. One of these antisera was found to be highly specific for the human bitter taste receptor TAS2R38. We further demonstrate that this antibody is able to detect heterologously expressed TAS2R38 protein on Western blots. The antiserum is, however, not able to interfere significantly with TAS2R38 function in cell based calcium imaging analyses. Most importantly, we were able to demonstrate the presence of TAS2R38 protein in human gustatory papillae. Using double immunofluorescence we show that TAS2R38-positive cells form a subpopulation of PLCbeta2 expressing cells. On a subcellular level the localization of this bitter taste receptor is neither restricted to the cell surface nor particularly enriched at the level of the microvilli protruding into the pore region of the taste buds, but rather evenly distributed over the entire cell body.
