The LUC7L Knockout Raji Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the Raji B lymphoblast line, engineered for loss of LUC7L function. LUC7L encodes a U1 snRNP-associated pre-mRNA splicing factor essential for 5?? splice site recognition. This heterogeneous pool of gene-disrupted cells avoids clonal biases and provides a robust model for studying splicing regulation. The CRISPR-mediated gene disruption introduces random indel mutations via non-homologous end joining, resulting in functional knockout without predetermining the editing pattern. Such polyclonal models are ideal for unbiased functional genomics screens and spliceosome studies.
Raji cells are an Epstein-Barr virus (EBV)-positive B lymphoblast line derived from Burkitt??s lymphoma, retaining key features of humoral immunity. They constitutively express B-cell markers and exhibit continuous proliferation driven by viral oncoproteins. Widely used in cancer biology and immunology, Raji cells offer a lymphoid context for examining how splicing factor perturbations affect B-cell physiology. Their suspension growth, high transfectability, and responsiveness to immune stimuli make them suitable for large-scale knockout studies, including arrayed pooled screens and detailed molecular phenotyping.
LUC7L functions within the U1 snRNP complex, interacting with U1 snRNA, U1-70K, U1-A, U1-C, and Sm proteins to define 5?? splice site selection. Upstream, its expression is controlled by general transcription factors and splicing-regulatory signals. Downstream, LUC7L modulates the splicing of numerous pre-mRNAs, including those encoding cell cycle regulators and apoptosis factors. Loss of LUC7L impedes U1 snRNP recruitment to nascent transcripts, causing intron retention and alternative exon usage. Consequently, the assembly of subsequent spliceosomal complexes (U2, U4/U6, U5) is compromised, and snRNP biogenesis via the SMN complex may be indirectly affected.
In the Raji B-lymphoma background, LUC7L knockout illuminates the pathological consequences of U1 snRNP dysfunction. Splicing factor mutations are prevalent in B-cell malignancies, and this model allows dissection of how altered 5?? splice site recognition promotes oncogenic gene expression. Disruption of LUC7L-dependent splicing may alter mRNA isoforms of critical lymphoma drivers or tumor suppressors, potentially influencing proliferation, survival, and immune evasion. The EBV-positive status further enables study of virus-host spliceosome interactions, which may reveal dependencies in latency maintenance. Thus, this polyclonal knockout system serves as a physiologically relevant platform for investigating splicing-driven mechanisms in lymphomagenesis.
Typical experimental applications include RT-qPCR and RNA-seq for transcriptome-wide splicing analysis, western blotting for LUC7L protein depletion, and co-immunoprecipitation of U1 snRNP components. Flow cytometry can assess changes in B-cell surface markers and apoptosis induction upon splicing disruption. These cells are also amenable to functional complementation assays, drug sensitivity screens with spliceosome or B-cell receptor inhibitors, and pooled CRISPR modifier screens to identify genetic interactions. Collectively, these tools empower in-depth studies of pre-mRNA processing in B-cell biology and cancer. For additional details, please contact Ascent Research.
