ChIP-Seq analysis of transcription factors CREB and C/EBP beta in vasopressin-responsive mouse renal collecting duct mpkCCD cells

Vasopressin, a peptide hormone, controls renal water excretion, largely through regulation of water channel aquaporin-2 (AQP2) in the renal collecting duct. There are two regulatory mechanisms of AQP2: 1) short-term regulation by membrane trafficking of AQP2; and 2) long-term regulation involving vasopressin-induced changes of protein abundance of AQP2 through regulation of gene transcription and protein half-life. Vasopressin binds a G protein-coupled receptor (V2R) activating a cyclic AMP/protein kinase A (PKA) signaling pathway. Sequentially, after activation of cAMP/PKA signaling, many of transcription factors involve gene transcription process. cAMP-response element binding protein (CREB) and cAMP-responsive transcription factor C/EBP beta are potential candidates for vaopressin-mediated regulation of Aqp2 gene transcription proviously reported. In the present study, genome-wide binding sites for two b-ZIP transcription factors CREB and C/EBP beta were identified in vasopressin-responsive mouse collecting duct mpkCCD cells using ChIP-Seq. To identify binding sites of transcription factors CREB and C/EBP beta in cultured mouse collecting duct mpkCCD cells, we carried out ChIP-seq for genome-wide distribution of CREB (n=4) and C/EBP beta (n=2). Observations were made both after 30 minutes treatment with the vasopressin analog dDAVP or vehicle.