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Biology subjects

Root, M.

Publications and source records attributed to Root, M..

3 recordsLinked to original sources

Human cytomegalovirus virion delivered UL14 is a viral tropism factor for epithelial cells

Infection with Human Cytomegalovirus (HCMV) can result in a significant burden of disease in those that are immunocompromised or immunonaive. HCMV encodes a repertoire of glycoproteins that facilitate its extensive viral tropism, some of which remain to be characterized. Currently, there is no effective vaccine or cure for HCMV, therefore emphasizing the need to identify viral proteins of critical function. UL14 was selected as an open reading frame of interest due to its high scoring on an in-silico prediction algorithm, as well as its conservation amongst CMVs. Our goal was to elucidate the function of this uncharacterized viral open reading frame. We hypothesized that UL14 functions in the establishment of infection in epithelial cells, due to its predicted structural similarity to UL141. This study demonstrates that HCMV UL14 is a glycosylated viral protein packaged with the virion. Importantly, the deletion of UL14 resulted in a significant reduction of viral growth in epithelial cells, whereas no growth defect was observed in fibroblasts. Mechanistically, we found this defect to be a result of post entry, pre-IE transcription in the establishment of infection, consistent with a defect endosomal escape. Taken together, our results suggest that UL14 functions in the establishment of infection in an epithelial cell-specific manner and may be a novel target for future vaccines or antiviral therapies. Author SummaryHCMV is found in a wide variety of human cells during the course of viral infection. As such, HCMV encodes several glycoprotein complexes that dictate tropism. In this work we report the identification of a novel glycoprotein, UL14, that is involved in establishing productive infections of epithelial cells, a common site of HCMV induced disease. We report that deletion of UL14 from the viral genome impacts its ability to infect ARPE19 cells at a stage indicative of viral events post viral entry but prior to viral transcriptional activation. Further, trans complementation of UL14 by expansion of mutant virus in cells expressing the viral glycoprotein, restore viral infectivity suggesting that UL14 mediates events early in viral infection. Importantly, the characterization of this viral envelope protein provides key insights into viral tropism and identifies a novel target for vaccine design and antiviral therapies.

microbiology↗

Screening metatranscriptomes for ultrastable RNA secondary structures reveals hidden bacteriophages and novel capsid nanomaterials

Metatranscriptomics has transformed our view of RNA bacteriophage diversity, revealing vast numbers of single-stranded RNA (ssRNA) phages whose protein capsids can be engineered for biotechnology applications. However, many ssRNA phages remain hidden from current detection methods, which require protein-level similarity to known phages. Here we show that RNA structure provides an additional signal for the detection of ssRNA phages in metatranscriptomes, including hidden phages missed by prior protein-based methods. By computationally folding each contig and screening for exceptionally stable RNA secondary structures, we find evidence of thousands of previously unrecognized phages encoding novel coat proteins. We express a library of 12,000 such coat proteins in E. coli and find that most assemble into nuclease-resistant capsids. We determine the 3D structure of one such capsid by cryo-electron microscopy and demonstrate that it can be disassembled and reassembled in vitro to package heterologous RNA--a key step toward repurposing these particles as RNA delivery vehicles. We compile the newly discovered ssRNA phages with previously known ones into a database that contains sequence and structural information for over 460,000 unique RNA molecules and over 100,000 distinct coat proteins, providing a comprehensive resource for microbiology and nanomaterials research.

biochemistry↗

Enhancing lipid production in plant cells through high-throughput genome editing and phenotyping via a scalable automated pipeline

Plant bioengineering is a time-consuming and labor-intensive process, with no guarantee of achieving the desired trait. Here we report a fast, automated, scalable, high-throughput pipeline for plant bioengineering (FAST-PB). FAST-PB achieves gene cloning, genome editing, and product characterization by integrating automated biofoundry engineering of callus and protoplast cells with single cell matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). We first demonstrate that FAST-PB can streamline the Golden Gate cloning process, with the capacity to construct 96 vectors in parallel. To prove the concept, using FAST-PB, we first found that PEG2050 significantly increases transfection efficiency by over 45%. To validate the pipeline, we established a reporter-gene-free method for CRISPR editing via mutation of HCF136, affecting cellular chlorophyll fluorescence. Next, we applied this pipeline for lipid production and found that diverse lipids were significantly enhanced up to sixfold through introducing multi-gene cassettes via CRISPR activation, and regenerated plant using this platform. Lastly, we harnessed FAST-PB to achieve high-throughput single-cell lipid profiling through the integration of MALDI-MS with the biofoundry, and differentiated engineered and unengineered cells using the single-cell lipidomics. These innovations massively increase the throughput of synthetic biology, genome editing, and metabolic engineering, and change what is possibly using single-cell metabolomics in plants.

synthetic biology↗