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Rose, J. K.

Publications and source records attributed to Rose, J. K..

5 recordsLinked to original sources

Spatiotemporal variation in cutin polymerization and remodeling mediated by GDSL-hydrolase enzymes during tomato fruit development

Land plants produce a cuticle, an extracellular hydrophobic layer that covers aerial organs and is involved in many critical protective roles, most notably in preventing desiccation. The predominant component of the cuticle is the lipidic polyester, cutin, which is deposited in the epidermal primary cell wall. Most of cutin of tomato fruit, a model for cuticle research, is polymerized by the extracellular GDSL-hydrolase enzyme CUTIN SYNTHASE-LIKE 1 (CUS1). However, other enzymes involved in cutin assembly remain to be identified and characterized. In this current study, we investigated whether other GDSL-hydrolases that are highly expressed in fruit epidermis might also contribute to cutin polymerization and restructuring. Candidates include homologs of Arabidopsis thaliana CUTICLE DESTRUCTIVE FACTOR 1 (CDEF1), which has been reported to catalyze cutin hydrolysis, as well as other phylogenetically diverse and distantly related GDSL-hydrolases. We determined that members of the CUS and CDEF families can catalyze the transesterification of cutin precursors in vitro, and can modify tomato fruit cutin structure in semi-in vivo assays. Tomato mutant knockout lines of CUS and CDEF genes generated by CRISPR/Cas9 and cross mutations with cus1 (previously cd1) were found to exhibit different fruit and flower phenotypes related to cutin assembly, including an effect on cutin monomer esterification, composition and content, cutin nanoridge formation in flowers, fruit cuticle permeability and permeance. Characterization of the mutant phenotypes, in combination with the enzyme analysis and bioassays, revealed distinct differences in the contribution of CUS and CDEF enzymes to cutin biosynthesis and remodeling. Our analysis also revealed unexpected spatiotemporal variation in cutin polymerization and structure coordinated by distinct GDSL-hydrolase enzymes over the fruit surface, which further suggests great complexity in cutin deposition and cuticle functions during organ development. HighlightsO_LICutin polymerization in tomato is catalyzed by coordinating the spatiotemporal expression of CUTIN SYNTHASE enzymes in different organs, including during fruit development. C_LIO_LIExtracellular cutin polymerization is not a function limited to the canonical CUTIN SYNTHASE family members but can be also be catalyzed by other GDSL-hydrolase enzymes, as suggested by evidence in vitro. C_LIO_LITomato CDEF enzymes, a clade within the GDSL-hydrolase superfamily, are involved in remodeling cutin structure during fruit development. C_LIO_LIThe biosynthesis and remodeling of cutin over the tomato fruit surface is spatially heterogeneous. C_LI

plant biology↗

Pharmacogenomics Guided Spaceflight: the intersection between space-flown drugs and space genes

Ten years ago, it was predicted that the multi-omics revolution would also revolutionize space pharmacogenomics. Current barriers related to the findable, accessible, interoperable, and reproducible use of space-flown pharmaceutical data have contributed to a lack of progress beyond application of earth-based principles. To directly tackle these challenges, we have produced a novel database of all the drugs flown into space, compiled from publicly available ontological and spaceflight-related datasets, to exemplify analyses for describing significant spaceflight-related targets. By focusing on mechanisms perturbed by spaceflight, we have provided a novel avenue for identifying the most relevant changes within the drug absorption, distribution, metabolism, and excretion pathways. We suggest a set of space genes, by necessity limited to available tissue types, that can be expanded and modified based on future tissue-specific and mechanistic-specific high-throughput assays. In sum, we provide the justification and a definitive starting point for pharmacogenomics guided spaceflight as a foundation of precision medicine, which will enable long-term human habitation of the Moon, Mars, and beyond. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=147 SRC="FIGDIR/small/575951v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@48f739org.highwire.dtl.DTLVardef@5ecdb0org.highwire.dtl.DTLVardef@121c93org.highwire.dtl.DTLVardef@1122b3f_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Callose deposition is essential for the completion of cytokinesis in the unicellular alga Penium margaritaceum

Cytokinesis in land plants involves the formation of a cell plate that develops into the new cell wall. Callose is a {beta}-1,3 glucan that transiently accumulates at later stages of cell plate development and is thought to stabilize the delicate membrane network of the cell plate as it expands. Cytokinetic callose deposition is currently considered specific to multicellular plant species as it has not been detected in unicellular algae. Here we present callose at the cytokinesis junction of the unicellular charophyte, Penium margaritaceum. Notably, callose deposition at the division plane of P. margaritaceum showed distinct, spatiotemporal patterns that could represent distinct roles of this polymer in cytokinesis and cell wall assembly. Pharmacological inhibition of cytokinetic callose deposition by Endosidin 7 treatment resulted in cytokinesis defects, consistent with the essential role for this polymer in P. margaritaceum cell division. Cell wall deposition and assembly at the isthmus zone was also affected by the absence of callose, demonstrating the dynamic nature of new wall assembly in P. margaritaceum. The identification of candidate callose synthase genes provides molecular evidence for callose biosynthesis in P. margaritaceum. The evolutionary implications of cytokinetic callose in this unicellular Zygnematopycean alga is discussed in the context of the conquest of land by plants. Summary StatementEvolutionarily conserved callose in Penium margaritaceum is essential for the completion of cytokinesis.

cell biology↗

Virus-like vesicles expressing multiple antigens for immunotherapy of chronic hepatitis B

Infection with hepatitis B virus (HBV) can initiate chronic hepatitis and liver injury, eventually progressing to liver fibrosis or cancer and causing more than 600,000 deaths each year worldwide. Current treatments for chronic hepatitis B, relying on nucleoside antivirals and interferon, are inadequate and leave an unmet need for immunotherapeutic approaches. This report describes virus-like vesicles (VLV), a form of self-amplifying RNA replicons, which express multiple HBV antigens (polymerase, core, and middle surface) from a single vector (HBV-VLV). The HBV-VLV induces HBV-specific T cell responses to all three HBV antigens. Immunization of naive mice with the multiantigen HBV-VLV renders them resistant to acute challenge with HBV delivered by adeno-associated virus (AAV). Using a chronic model of HBV infection by AAV delivery of HBV, we demonstrate immunotherapeutic potential of the multiantigen HBV-VLV in combination with DNA booster immunization, as 40% of the HBV-VLV-treated mice showed a decline of the serum HBV surface antigen below the detection limit and marked reduction in liver HBV RNA accompanied by induction of HBsAg-specific CD8 T cells. These results warrant further evaluation of multiantigen HBV-VLV for immunotherapy of chronic hepatitis B. IMPORTANCEMore than 240 million people worldwide are chronically infected with hepatitis B virus. Current therapies are not sufficiently effective and are often beyond reach in the developing world. We describe a virus-like vesicle-based immunotherapeutic vaccine that expresses three major antigens of hepatitis B virus as a self-amplifying RNA replicon. By incorporating three HBV antigens in a single vaccine, we ensure broad T cell responses. We demonstrate that immunization with this vaccine protects mice from hepatitis B virus in a model of acute challenge. Importantly, treatment with this vaccine shows 40% efficacy in a mouse model of chronic hepatitis B. Thus, this study paves the way for evaluation of the multi-antigen virus-like vesicles as a tool for immunotherapy of chronic hepatitis B.

immunology↗

Glycerol phosphate acyltransferase 6 controls filamentous pathogen interactions and cell wall properties of the tomato and Nicotiana benthamiana leaf epidermis

The leaf epidermal wall is covered by a cuticle, composed of cutin and waxes, which protects against dehydration and constitutes a barrier against pathogen attack. Cutin monomers are formed by the transfer of 16- or 18-carbon fatty acids to glycerol by glycerol-3-phosphate acyltransferase (GPAT) enzymes, which facilitates their transport to the plant surface. Here we address the dual functionality of pathogen-inducible Glycerol phosphate acyltransferase 6 (GPAT6) in controlling pathogen entry and dehydration in leaves. Silencing of Nicotiana benthamiana NbGPAT6a increased leaf susceptibility to the oomycetes Phytophthora infestans and P. palmivora, whereas stable overexpression of NbGPAT6a-GFP rendered leaves more resistant to infection. A loss-of-function mutation of the orthologous gene in tomato (Solanum lycopersicum), SlGPAT6, similarly resulted in increased susceptibility of leaves to Phytophthora infection concomitant with altered intracellular infection structure morphology. Conversely, Botrytis cinerea disease symptoms were reduced. Modulation of GPAT6 expression predominantly altered the outer cell wall of leaf epidermal cells. The impaired cell wall-cuticle continuum of tomato gpat6-a mutants resulted in increased water loss and these plants had fewer stomata. Our work highlights a hitherto unknown role for GPAT6-generated cutin monomers in controlling epidermal cell properties that are integral to leaf-microbe interactions and limit dehydration.

plant biology↗