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Dias, J. M. L.

Publications and source records attributed to Dias, J. M. L..

2 recordsLinked to original sources

Cell surface ribonucleoproteins cluster with heparan sulfate to regulate growth factor signaling

Receptor-ligand interactions govern a wide array of biological pathways, facilitating a cells ability to interrogate and integrate information from the extracellular space. Here, using an unbiased genome-wide knockout screen, we identify heparan sulfate proteoglycans (HSPGs) as a major component in the organizational mechanism of cell surface glycoRNA and cell surface RNA binding proteins (csRBPs). Cleavage of mature heparan sulfate chains, knockout of N- and 6-O-sulfotransferases, overexpression of endo-6-O-sulfatases, or the addition of exogenous heparan sulfate chains with high 2-O sulfation result in marked loss in glycoRNA-csRBP clustering in U2OS cells. Functionally, we provide evidence that signal transduction by HS-dependent growth factors such as VEGF-A165 is regulated by cell surface RNAs, and in vitro VEGF-A165, selectively interacts with glycoRNAs. Our findings uncover a new molecular mechanism of controlling signal transduction of specific growth factors across the plasma membrane by the regulated assembly of glycoRNAs, csRBPs, and heparan sulfate clusters.

molecular biology↗

Genetic modification of primary human B cells generates translationally-relevant models of high-grade lymphoma

Sequencing studies of Diffuse Large B Cell Lymphoma (DLBCL) have identified hundreds of recurrently altered genes. However, it remains largely unknown whether and how these mutations may contribute to lymphomagenesis, either individually or in combination. Existing strategies to address this problem predominantly utilize cell lines, which are limited by their initial characteristics and subsequent adaptions to prolonged in vitro culture. Here, we describe a novel co-culture system that enables the ex vivo expansion and viral transduction of primary human germinal center B cells. The incorporation of CRISPR/Cas9 technology enables high-throughput functional interrogation of genes recurrently mutated in DLBCL. Using a backbone of BCL2 with either BCL6 or MYC we have identified co-operating oncogenes that promote growth and survival, or even full transformation into synthetically engineered models of DLBCL. The resulting tumors can be expanded and sequentially transplanted in vivo, providing a scalable platform to test putative cancer genes and for the creation of mutation-directed, bespoke lymphoma models.

cancer biology↗