JeB001: Elucidation of the distal convoluted tubule transcriptome identified new candidate players in magnesium balance

ABSTRACT: The distal convoluted tubule (DCT) plays a key role in the fine-tuning of renal Mg2+ reabsorption. In recent years, hereditary magnesium (Mg2+) transport disorders have helped to identify important players in DCT Mg2+ homeostasis. Here, we report the Mg2+-sensitive transcriptional expression of the DCT transcriptome using gene expression microarray analysis. Mice expressing eGFP under a DCT-specific promoter were subjected to Mg2+-deficient or Mg2+-enriched diets. Subsequently, the Complex Object Parametric Analyzer and Sorter (COPAS) allowed isolation of eGFP-positive DCT cells. RNA extracts were subjected to pair-wise microarray analysis, high vs. low Mg2+. Of all genes in the genome, 46 were shown to be differentially expressed with a minimal fold-change of 2. Several known magnesiotropic genes, such as Trpm6 and Parvalbumin, were upregulated in the low Mg2+ fraction. Moreover, new genes were identified that are potentially involved in renal Mg2+ homeostasis. To confirm that the selected candidate genes are regulated by dietary Mg2+ availability, the expression levels of Slc41a3, Pcbd1, Tbc1d4 and Umod were determined by RT-PCR analysis. Indeed, all four genes were shown to be significantly upregulated in mice fed the Mg2+-deficient diet. In conclusion, by elucidating the Mg2+-sensitive DCT transcriptome, new candidate players in renal Mg2+ homeostasis were identified. RNA samples were isolated from PV-eGFP-positive tubules from mice fed on a low (L-samples) or high (H-samples) magnesium diet. Littermate H and L samples were labeled and put on mouse microarrays together. Two of the four sample sets were analyzed in dye-swap to compensate for dye-biases.

ORGANISM(S): Mus musculus

SUBMITTER: Marian Groot Koerkamp 

PROVIDER: E-GEOD-40208 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress