Biology subjects

Sanborn, O.

Publications and source records attributed to Sanborn, O..

3 recordsLinked to original sources

bioRxiv2026

ERV-derived dsRNAs induce stress granules that drive neural crest fate to initiate melanoma

Melanoma arises when melanocytes are oncogenically reprogrammed into neural crest-like cells, but what initiates this switch is unknown. Here we show that endogenous retrovirus (ERV)-derived double stranded RNAs (dsRNAs) induce stress granules (SGs) that drive this fate change. In zebrafish, melanoma progresses through a stage-specific ERV switch: zferv marks precursor cells before crestin activates in tumor cells. Both elements generate dsRNA that triggers eif2ak2-dependent SGs within precursor lesions and through transformation. SGs are tumorigenic as G3BP1 overexpression accelerates melanoma onset, whereas mosaic, melanocyte-specific g3bp1/2 knockout delays it. Small molecule-mediated inhibition of G3BP1/2 eliminates precursor lesions and reduces tumor burden. Similarly, blocking dsRNA sensing prevents SG formation and lowers melanoma incidence. Human nevi and melanomas show analogous, stage-specific ERV programs and SG assembly. In human melanoma cells, SGs sequester and translationally repress SOX10-regulating mRNAs, including the tumor suppressor KMT2D. Mosaic knockout of kmt2d in vivo enhances SOX10-driven neural crest reactivation. Thus, an ERV-SG axis establishes an oncogenic translatome that enables melanoma fate, with diagnostic and therapeutic potential.

cancer biology↗

bioRxiv2025

RBPscan: A Quantitative, In Vivo Tool for Profiling RNA-Binding Protein Interactions

RNA-binding proteins (RBPs) are essential regulators of gene expression at post-transcriptional level, yet obtaining quantitative insights into RBP-RNA interactions in vivo remains a challenge. Here we developed RBPscan, a method that integrates RNA editing with massively parallel reporter assays (MPRAs) to profile RBP binding in vivo. RBPscan fuses the catalytic domain of ADAR to the RBP of interest, using RNA editing of a recorder mRNA as a readout of binding events. We demonstrate its utility in zebrafish embryos, human cells, and yeast, where it quantifies binding strength, resolves dissociation constants, identifies high-specificity motifs for a variety of RBPs, and links binding affinities to their impact on mRNA stability. RBPscan also provides positional information of conserved and novel Pumilio-binding sites in lncRNA NORAD. With its simplicity, scalability, and compatibility across systems, RBPscan offers a versatile tool for investigating RBP-RNA interactions and complements established methods for studying post-transcriptional regulatory networks. GRAPHICAL ABSTARCT O_FIG O_LINKSMALLFIG WIDTH=153 HEIGHT=200 SRC="FIGDIR/small/631239v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@14e97d8org.highwire.dtl.DTLVardef@d30038org.highwire.dtl.DTLVardef@b39459org.highwire.dtl.DTLVardef@1d0679f_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

bioRxiv2021

Optimization of Non-Coding Regions Improves Protective Efficacy of an mRNA SARS-CoV-2 Vaccine in Nonhuman Primates

The CVnCoV (CureVac) mRNA vaccine for SARS-CoV-2 has recently been evaluated in a phase 2b/3 efficacy trial in humans. CV2CoV is a second-generation mRNA vaccine with optimized non-coding regions and enhanced antigen expression. Here we report a head-to-head study of the immunogenicity and protective efficacy of CVnCoV and CV2CoV in nonhuman primates. We immunized 18 cynomolgus macaques with two doses of 12 ug of lipid nanoparticle formulated CVnCoV, CV2CoV, or sham (N=6/group). CV2CoV induced substantially higher binding and neutralizing antibodies, memory B cell responses, and T cell responses as compared with CVnCoV. CV2CoV also induced more potent neutralizing antibody responses against SARS-CoV-2 variants, including B.1.351 (beta), B.1.617.2 (delta), and C.37 (lambda). While CVnCoV provided partial protection against SARS-CoV-2 challenge, CV2CoV afforded robust protection with markedly lower viral loads in the upper and lower respiratory tract. Antibody responses correlated with protective efficacy. These data demonstrate that optimization of non-coding regions can greatly improve the immunogenicity and protective efficacy of an mRNA SARS-CoV-2 vaccine in nonhuman primates.

immunology↗