{"database":"GEO","file_versions":[{"headers":{"Content-Type":["application/json"]},"body":{"files":{"Other":["ftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE326nnn/GSE326336/"]},"type":"primary"},"statusCode":"OK","statusCodeValue":200}],"scores":null,"additional":{"omics_type":["Transcriptomics"],"species":["Mus musculus"],"gds_type":["Expression profiling by high throughput sequencing"],"full_dataset_link":["https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE326336"],"repository":["GEO"],"entry_type":["GSE"],"additional_accession":[]},"is_claimable":false,"name":"CRISPR/Cas9 screening reveals key role of STK11/LKB1 in vasopressin-mediated regulation of Aqp2 transcription","description":"Identification of signaling networks is an essential goal in systems biology. Here, we use CRISPR knockout screening (employing a whole kinome sgRNA library) to identify functionally critical protein kinases in a well-studied Gs-dependent G-protein coupled receptor (GPCR)-signaling model, namely the vasopressin V2 receptor (V2R). Screening was done using a specially-designed fluorescence-based reporter cell line with green-fluorescent protein (GFP) co-transcribed with Aqp2, a gene whose transcription is dependent on vasopressin-mediated activation of protein kinase A (PKA). The reporter line endogenously expresses V2R. Positive regulators (n=16) included PKA-catalytic subunit α (but not β). Mark2 (Par1b) and Dyrk1a (minibrain homolog). Negative regulators (n=13) included PKA-regulatory subunit type Iα, Stk11 (liver kinase B1 [LKB1]), and three TGF-β receptor subunits (Tgfbr1, Tgfbr2, Tgfbr3) (see https://esbl.nhlbi.nih.gov/Databases/Kinome-CRISPR-screen/ for full list). Dyrk1a and Stk11/LKB1 knockout cell lines were created for further study. Dyrk1a knockout cell lines failed to express AQP2 protein and exhibited a profound decrease in AQP2 mRNA. RNA-sequencing demonstrated widespread increases in cell-cycle transcripts, with a general defect in cell differentiation, accounting for AQP2 loss. Stk11/LKB1 knockout lines displayed marked increases in AQP2 protein and mRNA. RNA-sequencing and phospho-proteomic findings point to a signaling model in which Stk11/LKB1- and PKA-mediated phosphorylation events exert counteracting effects on the activities of cAMP-responsive transcriptional coactivator (CRTC) proteins. Finally, additional studies confirmed that TGF-β exposure to un-transformed cells results in a profound decrease in AQP2 mRNA abundance along with most recognized differentiation markers, consistent with our prior conclusion that TGF-β represses Aqp2 gene expression by inducing epithelial-mesenchymal transition.","dates":{"publication":"2026/03/30"},"accession":"GSE326336","cross_references":{"GSM":["GSM9629585","GSM9629584","GSM9629587","GSM9629586","GSM9629581","GSM9629580","GSM9629583","GSM9629582","GSM9629608","GSM9629607","GSM9629609","GSM9629604","GSM9629603","GSM9629606","GSM9629605","GSM9629600","GSM9629589","GSM9629588","GSM9629602","GSM9629569","GSM9629601","GSM9629596","GSM9629574","GSM9629573","GSM9629595","GSM9629576","GSM9629598","GSM9629597","GSM9629575","GSM9629570","GSM9629592","GSM9629591","GSM9629594","GSM9629572","GSM9629593","GSM9629571","GSM9629590","GSM9629611","GSM9629578","GSM9629610","GSM9629599","GSM9629577","GSM9629579","GSM9629612"],"GPL":["34328"],"GSE":["326336"],"taxon":["Mus musculus"]}}