The JPH1 Knockout HT29 Polyclonal Cells represent a CRISPR/Cas9-mediated gene disruption model targeting the human JPH1 locus in the HT29 colorectal adenocarcinoma cell line. This product consists of a polyclonal population of cells carrying diverse JPH1 loss-of-function alleles, providing a robust tool for studying junctophilin-1 deficiency without clonal bias.
HT29 is a human colorectal adenocarcinoma cell line isolated from a primary tumor of a 44-year-old female. It is extensively used in cancer research to investigate oncogenic signaling, drug response, and apoptosis mechanisms. These cells express key components of calcium signaling pathways, including inositol 1,4,5-trisphosphate receptors (IP3Rs) and store-operated calcium entry machinery, making them particularly suitable for dissecting JPH1 function.
Junctophilin-1 (JPH1) belongs to the junctophilin family of membrane-tethering proteins that establish junctional membrane complexes between the plasma membrane and the endoplasmic/sarcoplasmic reticulum. This structural role is critical for the functional coupling of cell surface voltage-gated or receptor-operated calcium channels with intracellular calcium release channels such as RyR and IP3R. JPH1 directly interacts with type 1 ryanodine receptors (RYR1), type 2 ryanodine receptors (RYR2), and inositol 1,4,5-trisphosphate receptor type 1 (ITPR1), as well as calmodulin, to scaffold calcium signaling microdomains. In HT29 cells, JPH1 expression is regulated by Wnt pathway components and calcium/calmodulin-dependent kinases, potentially linking it to colorectal cancer signaling networks. Disruption of JPH1 alters the spatial organization of calcium release units, thereby affecting downstream effectors including NFAT transcription factors and caspase-dependent apoptosis pathways.
In the context of colorectal cancer, HT29 cells rely on intact calcium signaling for the execution of apoptotic programs and the regulation of transcription factors such as NFAT. Loss of JPH1 in this polyclonal knockout model allows researchers to examine how the uncoupling of plasma membrane?CER junctions impacts store-operated calcium entry, intracellular calcium oscillations, and the activation of calcium-dependent transcriptional responses. This model is particularly relevant for studying the interplay between calcium microdomains and cancer cell survival, as well as for evaluating the potential dysregulation of JPH1 expression observed in colorectal tumors. Moreover, the polyclonal nature of the knockout population more closely mimics the heterogeneous genetic landscape of tumors, providing a physiologically relevant system for pharmacological and genetic screens.
Typical applications of the JPH1 Knockout HT29 Polyclonal Cells include quantitative analysis of cytosolic calcium dynamics using ratiometric dyes such as Fura-2, assessment of store-operated calcium entry, and functional dissection of NFAT-driven transcription via luciferase reporter constructs. This model also enables investigation of calcium-dependent apoptosis by Annexin V staining and MTT-based viability assays under chemotherapeutic challenge, providing insight into how junctophilin-1 modulates drug sensitivity. Furthermore, the polyclonal population can be employed in co-culture and 3D organoid systems to study tumor microenvironment interactions. For ordering information, technical support, or to discuss custom applications, please contact Ascent Research.
