Transcriptome of a mouse kidney cortical collecting duct cell line: Effects of aldosterone and vasopressin

Aldosterone and vasopressin are responsible for the final adjustment of sod ium and water reabsorption in the kidney. In principal cells of the kidney cortical collecting duct (CCD), the integral response to aldosterone and th e long-term functional effects of vasopressin depend on transcription. In t his study, we analyzed the transcriptome of a highly differentiated mouse c lonal CCD principal cell line (mpkCCD(cl4)) and the changes in the transcri ptome induced by aldosterone and vasopressin. Serial analysis of gene expre ssion (SAGE) was performed on untreated cells and on cells treated with eit her aldosterone or vasopressin for 4 h. The transcriptomes in these three e xperimental conditions were determined by sequencing 169,721 transcript tag s from the corresponding SAGE libraries. Limiting the analysis to tags that occurred twice or more in the data set, 14,654 different transcripts were identified, 3,642 of which do not match known mouse sequences. Statistical comparison (at P < 0.05 level) of the three SAGE libraries revealed 34 AITs (aldosterone-induced transcripts), 29 ARTs (aldosterone-repressed transcri pts), 48 VITs (vasopressin-induced transcripts) and 11 VRTs (vasopressin-re pressed transcripts). A selection of the differentially-expressed, hormone- specific transcripts (5 VITs, 2 AITs and 1 ART) has been validated in the m pkCCD(cl4) cell line either by Northern blot hybridization or reverse trans cription-PCR. The hepatocyte nuclear transcription factor HNF-3<alpha> (VIT 39), the receptor activity modifying protein RAMP3 (VIT48), and the glucoco rticoid-induced leucine zipper protein (GILZ) (AIT28) are candidate protein s playing a role in physiological responses of this cell line to vasopressi n and aldosterone.