👤 T Görg

The structural-functional organization of ammonia and glutamine metabolism in the liver acinus involves highly specialized hepatocyte subpopulations like glutamine synthetase (GS) expressing perivenous hepatocytes (scavenger cells). However, this cell population has not yet been characterized extensively regarding expression of other genes and potential subpopulations. This was investigated in the present study by proteome profiling of periportal GS-negative and perivenous GS-expressing hepatocytes from mouse and rat. Apart from established markers of GS Show less

Neuromedin B has been shown to exert an inhibiting effect on food consumption in rats. The corresponding gene NMB maps to chromosome 15q22.3-q23, a region expected to contain a gene for the Bardet-Biedl syndrome type 4 (BBS4). Based on its map position and the putative function of the encoded peptide, NMB can be considered as a candidate gene both for BBS4 and the development of human obesity. To examine its involvement in these phenotypes, we determined the genomic structure of human NMB, and performed a mutation screen in its coding region. In genomic DNA of six BBS4 patients and in a large population sample, two sequence variants were detected: a g.253C-->A transversion creating a P73T substitution and a g.401G-->A silent mutation changing the stop codon TGA into stop codon TAA. A case-control study with 92 extremely obese patients and 94 underweight students revealed a significant association between the g.401G-->A polymorphism and body weight (adjustedp = 0.03), which was confirmed in a validation sample consisting of 95 extremely obese patients, and 95 normal weight and 48 underweight individuals (Mann-Whitney p = 0.02). These results suggest a contribution of NMB or a gene in its close vicinity to genetic weight control in humans. Show less