MGRN1 Knockout Raji Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human Raji B lymphoblastoid line, designed to disrupt the MGRN1 gene encoding an E3 ubiquitin ligase. This heterogeneous pool provides a robust loss-of-function model for studying MGRN1-dependent processes in a lymphoid background, enabling investigation of endosomal sorting, ubiquitin-dependent signaling, and melanocortin receptor regulation without clonal selection artifacts.
The Raji host cell line is a classic model of Burkitt??s lymphoma, exhibiting an EBV-positive, male, suspension-growth phenotype. These transformed B lymphocytes are widely used for their rapid proliferation, stable antigen presentation, and active endocytic pathways, making them ideal for exploring oncogenic mechanisms and trafficking processes central to B-cell receptor signaling and immune surveillance.
MGRN1 (Mahogunin Ring Finger 1) is an E3 ubiquitin ligase that regulates the endosomal sorting complex required for transport (ESCRT) pathway and melanocortin 1 receptor (MC1R) signaling. It directly ubiquitinates TSG101, a critical ESCRT-I component, and interacts with Hsp70, Hsp90, ATXN3, and parkin. MGRN1 is activated by heat shock stress and MC1R ligands like ??-MSH, leading to degradation of MC1R and modulation of MITF transcription factor activity. Loss of MGRN1 disrupts endosomal trafficking, receptor turnover, and stress responses, with implications for pigmentation and neurodegeneration.
In Raji B cells, MGRN1 knockout enables dissection of ubiquitin-proteasome and endosomal pathway intersections with lymphocyte functions. B lymphocytes depend on precise endosomal sorting for antigen processing and presentation via MHC class II, as well as B-cell receptor signaling. Disruption of MGRN1 may perturb ESCRT-I-dependent trafficking, altering immune receptor degradation and signaling, thereby providing insights into lymphomagenesis and EBV-driven oncogenesis.
This knockout model supports applications such as co-immunoprecipitation to assess TSG101 and Hsp70 interactions, flow cytometry for MC1R surface expression, and ubiquitination assays. Endocytosis assays with transferrin uptake reveal trafficking defects, while Western blotting and RT-qPCR monitor ESCRT-I subunits and MITF. The cells facilitate studies of melanocortin signaling in lymphoma and chaperone-mediated autophagy. For more information, contact Ascent Research.
