The ARHGDIB Knockout HT29 Polyclonal Cells consist of a CRISPR/Cas9-edited polyclonal population of HT29 cells with targeted disruption of the ARHGDIB gene. This loss-of-function model enables studies of Rho GDP dissociation inhibitor beta (ARHGDIB/GDI??) in colorectal epithelial biology. The polyclonal format retains heterogeneous genetic background, reducing clonal bias while ensuring effective gene knockout at the population level. CRISPR/Cas9-mediated gene disruption abrogates ARHGDIB expression, abolishing negative regulation of Rho family GTPases and permitting constitutive downstream signaling.
The HT29 parental cell line is a well-characterized model of human colorectal adenocarcinoma, originally derived from a primary tumor of a 44-year-old female patient. HT29 cells display epithelial morphology and can form polarized monolayers, making them ideal for studying intestinal barrier function, mucus secretion, and the molecular mechanisms of colorectal cancer. This cell line provides a physiologically relevant background for examining ARHGDIB function in colon carcinoma.
ARHGDIB encodes Rho GDP dissociation inhibitor beta, which sequesters inactive GDP-bound Rho proteins (RhoA, Rac1, Cdc42) in the cytosol, preventing activation by GEFs such as Vav and Tiam1 and inhibiting membrane association. ARHGDIB is regulated by integrin-mediated adhesion, growth factor receptors (EGFR, PDGFR), Src kinase, and PKC. Loss of ARHGDIB leads to constitutive Rho GTPase activation, triggering effectors ROCK, PAK, and WAVE complex, and transcriptional responses via SRF, NF-??B, and AP-1. This dysregulates actin cytoskeleton dynamics, cell migration, adhesion, and proliferation.
In HT29 colorectal adenocarcinoma cells, ARHGDIB knockout drives constitutive Rho family signaling, directly relevant to oncogenic transformation and metastasis. Enhanced activity of RhoA, Rac1, and Cdc42 promotes actin remodeling, increased migration, and altered adhesion??phenotypes associated with invasive colorectal cancer. This model is valuable for dissecting ARHGDIB’s role in epithelial polarity, barrier integrity, and chemokine signaling, and for exploring crosstalk with Src kinase and integrin pathways commonly dysregulated in colorectal cancer.
This KO model supports diverse assays such as GST-pull down for Rho GTPase activation, phalloidin staining for actin cytoskeleton visualization, wound healing and Transwell migration assays, adhesion and proliferation assays (MTS, BrdU), RNA-seq transcriptomic profiling, and phospho-signaling analysis of p38 and JNK. The cells are suitable for drug screening to identify metastasis inhibitors and for functional genomics studies. For further technical details, contact Ascent Research.
