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Based on the p426 series of expression vectors developed by Mumberg et al. (Gene 156, 119-122, ), we have generated a set of plasmids that allow the glucose-dependent expression of target genes in the yeast, Saccharomyces cerevisiae. The ADH1 promoter in plasmid p426-ADH1 was replaced by the 1-kb 5′-region from either of the following genes: HXK1, YGR243, HXT4 and HXT7. Expression mediated by the respective 5′-regions was monitored with EGFP, yEGFP3-CLN2pest and TurboGFP as marker genes. Fluorescence is induced 2.7-fold using the HXK1, 2.3-fold using the YGR243-, 5-fold using the HXT7- and 12.6-fold using the HXT4 5′-regions upon depletion of glucose to a concentration of <0.5 g/l. [ABSTRACT FROM AUTHOR]

Linkage analysis and congenic mapping have localized 18 loci ( Idd1-18 ) that contribute to the development of autoimmune type 1 diabetes in the nonobese diabetic (NOD) mouse. By using a congenic NOD strain which possesses recombinant MHC from a closely related CTS strain, a susceptible region ( Idd16 ) was mapped to the segment adjacent to, but distinct from class II A and E genes ( Idd1 ). The tumor necrosis factor α gene ( Tnf ), which is located within the Idd16 region, has been suspected to be a candidate gene for type 1 diabetes in the NOD mouse. Although the protein-coding region in Tnf has been sequenced in the NOD mouse and its related strains, the complete upstream region (approximately 1400 bp, including the 5′-untranslated region) has not yet been studied. To study the possible contribution of the transcriptional regulation of Tnf to susceptibility to type 1 diabetes, we determined the complete nucleotide sequences of the NOD strain and its related strain, CTS, in comparison with the non-diabetic control strain, C57BL/6. The nucleotide sequence of the 5′-upstream region in the NOD mouse was identical to that in the C57BL/6 mouse, but different from that in the CTS mouse. In particular, a C to A substitution at position 3408 in the CTS mouse creates a new GATA family binding site, which may be responsible for the lower incidence of type 1 diabetes in the NOD. CTS-H-2 congenic strain despite the presence of the same class II MHC. [ABSTRACT FROM AUTHOR]

We analyzed the whole-genome experimental maps of nucleosomes in Drosophila melanogaster and classified genes by the expression level in S2 cells (RPKM value, reads per kilobase million) as well as the number of tissues in which a gene was expressed (breadth of expression, BoE). Chromatin in 5′-regions of genes we classified on four states according to the hidden Markov model (4HMM). Only the Aquamarine chromatin state we considered as Active, while the rest three states we defined as Non-Active. Surprisingly, about 20/40% of genes with 5′-regions mapped to Active/Non-Active chromatin possessed the minimal/at least modest RPKM and BoE. We found that regardless of RPKM/BoE the genes of Active chromatin possessed the regular nucleosome arrangement in 5′-regions, while genes of Non-Active chromatin did not show respective specificity. Only for genes of Active chromatin the RPKM/BoE positively correlates with the number of nucleosome sites upstream/around TSS and negatively with that downstream TSS. We propose that for genes of Active chromatin, regardless of RPKM value and BoE the nucleosome arrangement in 5′-regions potentiates transcription, while for genes of Non-Active chromatin, the transcription machinery does not require the substantial support from nucleosome arrangement to influence gene expression. [ABSTRACT FROM AUTHOR]