The FTSJ1 Knockout Raji Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the Raji human B lymphocyte line, with targeted disruption of the FTSJ1 gene. This polyclonal pool offers a heterogeneous loss-of-function model for studying FTSJ1 ablation in B cells, avoiding clonal artifacts and enabling population-level functional analyses.
Raji cells are an EBV-positive human Burkitt lymphoma B lymphocyte line maintained in suspension culture, well-established for studying humoral immunity, antibody production, and antigen presentation. Derived from a Burkitt lymphoma, these cells exhibit high proliferation rates and express characteristic B cell markers, making them a valuable model for immunological and cancer research. Their capacity to undergo activation and secrete immunoglobulins provides a functional context for assessing the impact of genetic modifications on B cell physiology.
FTSJ1 encodes a tRNA 2′-O-methyltransferase that catalyzes S-adenosylmethionine-dependent 2′-O-methylation of tRNAPhe and tRNATrp at position 32, stabilizing tRNAs and ensuring translation fidelity of codon-biased mRNAs. It functions within the FMRP translational control network, interacting with S-adenosylmethionine, THUMP domain-containing proteins, and the FMRP ribonucleoprotein complex that includes FMRP, CYFIP1, and eIF4E. FTSJ1 activity is regulated upstream by FMRP and neuronal activity-dependent transcription factors, while downstream it modulates translation of synaptic plasticity-related proteins. Knockout abolishes tRNA methylation, destabilizing tRNAs and altering protein synthesis from mRNAs with specific codon usage, with potential impacts on B cell growth and antibody production.
In Raji B cells, loss of FTSJ1-mediated tRNA methylation may disrupt the proteome, affecting B cell receptor signaling, immunoglobulin synthesis, and proliferation. The polyclonal knockout pool allows population-level studies reflecting heterogeneous gene disruption, mimicking more physiologically varied conditions than clonal lines. Key experimental readouts include RiboMeth-seq to quantify 2′-O-methylation, western blotting for FTSJ1 expression, tRNA stability assays, polysome profiling to assess translational activity, cell proliferation assays, and flow cytometry for B cell surface markers.
Researchers can utilize this model to systematically evaluate the consequences of tRNA hypomodification on B cell growth, differentiation, and antibody secretion. It also serves as a platform for chemical screening to identify modulators of the FMRP-FTSJ1 axis, with potential implications for neurodevelopmental disorder therapies. Epitranscriptomic profiling may reveal codon-biased translational alterations linked to immune dysfunction, bridging neurobiology and immunology. For further details, please contact Ascent Research.
