Eight nuclear microsatellite loci were identified using the method of microsatellite-enriched libraries in the glasswort genus Salicornia. These markers yield specific alleles for discriminating ...diploid and tetraploid lineages and thus provide a reliable and efficient tool for routine determination of ploidy level in the genus. Within both the diploid and tetraploid lineages, the microsatellites further display a clear biogeographic signal. A significant partitioning of genetic differentiation was found between the diploid populations (Fst = 0.31; p < 0.001). The new microsatellite markers described here thus offer the appropriate amount of variation to address issues of species delimitation and biogeographic history in the genus.
The Rev-erb and retinoic acid-related orphan receptors (ROR) are two related families of orphan nuclear receptors that recognize similar response elements but have opposite effects on transcription. ...Recently, the Rev-erbα gene promoter has been characterized and shown to harbor a functional Rev-erbα-binding site known as Rev-DR2, responsible for negative feedback down-regulation of promoter activity by Rev-erbα itself. The present study aimed to investigate whether Rev-erbα gene expression is regulated by RORα. Gel shift analysis demonstrated thatin vitro translated hRORα1 protein binds to the Rev-DR2 site, both as monomer and dimer. Chromatin immunoprecipitation assays demonstrated that binding of RORα to this site also occurred in vivo in human hepatoma HepG2 cells. The Rev-DR2 site was further shown to be functional as it conferred hRORα1 responsiveness to a heterologous promoter and to the natural human Rev-erbαgene promoter in these cells. Mutation of this site in the context of the natural Rev-erbα gene promoter abolished its activation by RORα, indicating that this site plays a key role in hRORα1 action. Finally, adenoviral overexpression of hRORα1 in HepG2 cells led to enhanced hRev-erbα mRNA accumulation, further confirming the physiological importance of RORα1 in the regulation of Rev-erbα expression.
The Rev-erb and retinoic acid-related orphan receptors (ROR) are two related families of orphan nuclear receptors that recognize similar response elements but have opposite effects on transcription. ...Recently, the Rev-erbalpha gene promoter has been characterized and shown to harbor a functional Rev-erbalpha-binding site known as Rev-DR2, responsible for negative feedback down-regulation of promoter activity by Rev-erbalpha itself. The present study aimed to investigate whether Rev-erbalpha gene expression is regulated by RORalpha. Gel shift analysis demonstrated that in vitro translated hRORalpha1 protein binds to the Rev-DR2 site, both as monomer and dimer. Chromatin immunoprecipitation assays demonstrated that binding of RORalpha to this site also occurred in vivo in human hepatoma HepG2 cells. The Rev-DR2 site was further shown to be functional as it conferred hRORalpha1 responsiveness to a heterologous promoter and to the natural human Rev-erbalpha gene promoter in these cells. Mutation of this site in the context of the natural Rev-erbalpha gene promoter abolished its activation by RORalpha, indicating that this site plays a key role in hRORalpha1 action. Finally, adenoviral overexpression of hRORalpha1 in HepG2 cells led to enhanced hRev-erbalpha mRNA accumulation, further confirming the physiological importance of RORalpha1 in the regulation of Rev-erbalpha expression.
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