The GRIPAP1 Knockout SK-HEP-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the SK-HEP-1 human liver adenocarcinoma cell line, carrying targeted disruption of the GRIPAP1 gene. This loss-of-function model provides a null background for exploring GRIPAP1-mediated processes in a non-neuronal hepatic carcinoma context, enabling functional genomics studies, pathway dissection, and drug target validation without confounding wild-type protein activity. The polyclonal format captures editing heterogeneity, offering a robust system for reproducible experimental outcomes.
SK-HEP-1 cells, originally established from the ascites of a patient with liver adenocarcinoma, are widely used as a model for hepatocellular carcinoma due to their rapid growth, well-characterized proteome, and responsiveness to metabolic and pharmacological stimuli. These adherent epithelial cells express hepatic markers and support investigation of endosomal trafficking, signal transduction, and cell adhesion dynamics, making them an optimal host for examining the non-synaptic functions of GRIPAP1.
GRIPAP1 is a multidomain scaffold protein and guanine nucleotide exchange factor (GEF) for Ras, critically involved in AMPA receptor recycling and Ras-MAPK signaling cascades. It directly binds the PDZ domain protein GRIP1, the AMPA receptor subunit GluA2, the kinesin heavy chain KIF5, and endosomal regulators including Rab4, PICK1, NSF, and clathrin, thereby coupling motor-driven transport of receptor-containing vesicles to endosomal sorting. Upstream signals such as neuronal activity, protein kinase A (PKA), calcium influx, and BDNF-TrkB receptor activation converge on GRIPAP1, while downstream it activates Ras, MEK, and ERK1/2 and controls surface levels of AMPA receptor subunits GluA1 and GluA2. This molecular network underpins activity-dependent synaptic plasticity but may also serve analogous trafficking and signaling functions in non-neuronal cells.
Although GRIPAP1 is predominantly studied in the nervous system, its expression in SK-HEP-1 liver adenocarcinoma cells hints at broader roles in vesicular trafficking and Ras-dependent signal transduction. This knockout cell population permits rigorous dissection of GRIPAP1??s contributions to endosomal dynamics, receptor recycling, and MAPK cascade regulation within a liver cancer context, potentially revealing connections to cell proliferation, migration, and metabolic reprogramming that are characteristic of malignant hepatocytes.
Key experimental applications include co-immunoprecipitation and immunoblotting to characterize GRIPAP1 interaction networks in hepatic cells; Ras-GTPase activity assays and phospho-ERK1/2 analysis to quantify MAPK pathway output; immunofluorescence and confocal imaging to visualize endosomal compartmentalization and receptor trafficking; and functional assays monitoring cell viability, migration, and metabolism. These tools support mechanistic investigations into non-neuronal GRIPAP1 biology and therapeutic target evaluation. For further technical information and order inquiries, please contact Ascent Research.
