Pre-set extrusion bioprinting for multiscale heterogeneous tissue structure fabrication

Recent advances in three-dimensional bioprinting technology have led to various attempts in fabricating human tissue-like structures. However, current bioprinting technologies have limitations for creating native tissue-like structures. To resolve these issues, we developed a new pre-set extrusion bioprinting technique that can create heterogeneous, multicellular, and multimaterial structures simultaneously. The key to this ability lies in the use of a precursor cartridge that can stably preserve a multimaterial with a pre-defined configuration that can be simply embedded in a syringe-based printer head. The multimaterial can be printed and miniaturized through a micro-nozzle without conspicuous deformation according to the pre-defined configuration of the precursor cartridge. Using this system, we fabricated heterogeneous tissue-like structures such as spinal cords, hepatic lobule, blood vessels, and capillaries. We further obtained a heterogeneous patterned model that embeds HepG2 cells with endothelial cells in a hepatic lobule-like structure. In comparison with homogeneous and heterogeneous cell printing, the heterogeneous patterned model showed a well-organized hepatic lobule structure and higher enzyme activity of CYP3A4. Therefore, this pre-set extrusion bioprinting method could be widely used in the fabrication of a variety of artificial and functional tissues or organs

第774回 千葉医学会例会・第二内科例会 54.

InterProScan results. InterProScan [34] queries sequences against 16 member databases enabling protein classification by family as well as by conserved domains; the number of annotations and the percent of sequences receiving annotations varied across the different databases. (XLSX 32 kb

Comparative transcriptome analysis on wild-simulated ginseng of different age revealed possible mechanism of ginsenoside accumulation

Panax ginseng is one of the most famous pharmaceutical plants in Asia. Ginseng plants grown in mountain have longer longevity which ensures higher accumulation of ginsenoside components than those grown in farms. However, wild-simulated ginseng over certain age cannot be easily distinguished in morphology. To identify transcriptomic mechanism of ginsenoside accumulation in older wild-simulated ginseng without large phenotype change, we performed comparative transcriptome analysis for leaf, shoot, and root tissues of 7-yr-old and 13yr-old wild-simulated ginseng. Of 559 differentially expressed genes (DEGs) in comparison between 7-yr-old and 13yr-old wild-simulated ginseng, 280 leaf-, 103 shoot-, and 164 root-mainly expressing genes were found to be changed in transcript level according to age. Functional analysis revealed that pentose-phosphate shunt and abscisic acid responsive genes were up-regulated in leaf tissues of 7-yr-old ginseng while defense responsive genes were up-regulated in root tissues of 13-yr-old ginseng. Quantitative real-time PCR revealed that jasmonic acid responsive genes, ERDL6, and some UGTs were up-regulated in 13-yr-old ginseng in higher order lateral root tissues. These data suggest that bacterial stimulation in mountain region can enhance the expression of several genes which might support minor ginsenoside biosynthesis. © 2023 Elsevier Masson SAS11Nsciescopu

Arabidopsis ABCG27 plays an essential role in flower and leaf development by modulating abscisic acid content

Abscisic acid (ABA) is a phytohormone that mediates stress responses and regulates plant development. Several ATP-binding cassette (ABC) transporters in the G subfamily of ABC (ABCG) proteins have been reported to transport ABA. We investigated whether there are any other ABCG proteins that mediate plant developmental processes regulated by ABA in Arabidopsis (Arabidopsis thaliana). The ABCG27 gene was upregulated in response to exogenous ABA treatment. The abcg27 knockout mutant exhibited two developmental defects: epinastic leaves and abnormally long pistils, which reduced fertility and silique length. ABCG27 expression was induced 3-fold when flower buds were exposed to exogenous ABA, and the promoter of ABCG27 had two ABA-responsive elements. ABA content in the pistil and true leaves were increased in the abcg27 knockout mutant. Detached abcg27 pistils exposed to exogenous ABA grew longer than those of the wild-type control. ABCG27 fused to GFP localized to the plasma membrane when expressed in Arabidopsis mesophyll protoplasts. A transcriptome analysis of the pistils and true leaves of the wild type and abcg27 knockout mutant revealed that the expression of organ development-related genes changed in the knockout mutant. In particular, the expression of trans-acting small interference (ta-si) RNA processing enzyme genes, which regulate flower and leaf development, was low in the knockout mutant. Together, these results suggest that ABCG27 most likely function as an ABA transporter at the plasma membrane, modulating ABA levels and thereby regulating the development of the pistils and leaves under normal, non-stressed conditions

Orthologs of the Class A4 Heat Shock Transcription Factor HsfA4a Confer Cadmium Tolerance in Wheat and Rice[C][W]

Cadmium (Cd) is a widespread soil pollutant; thus, the underlying molecular controls of plant Cd tolerance are of substantial interest. A screen for wheat (Triticum aestivum) genes that confer Cd tolerance to a Cd hypersensitive yeast strain identified Heat shock transcription factor A4a (HsfA4a). Ta HsfA4a is most similar to the class A4 Hsfs from monocots. The most closely related rice (Oryza sativa) homolog, Os HsfA4a, conferred Cd tolerance in yeast, as did Ta HsfA4a, but the second most closely related rice homolog, Os HsfA4d, did not. Cd tolerance was enhanced in rice plants expressing Ta HsfA4a and decreased in rice plants with knocked-down expression of Os HsfA4a. An analysis of the functional domain using chimeric proteins constructed from Ta HsfA4a and Os HsfA4d revealed that the DNA binding domain (DBD) of HsfA4a is critical for Cd tolerance, and within the DBD, Ala-31 and Leu-42 are important for Cd tolerance. Moreover, Ta HsfA4a–mediated Cd resistance in yeast requires metallothionein (MT). In the roots of wheat and rice, Cd stress caused increases in HsfA4a expression, together the MT genes. Our findings thus suggest that HsfA4a of wheat and rice confers Cd tolerance by upregulating MT gene expression in planta

Prolonged Exposure to High Temperature Inhibits Shoot Primary and Root Secondary Growth in Panax ginseng

High temperature is one of the most significant abiotic stresses reducing crop yield and quality by inhibiting plant growth and development. Global warming has recently increased the frequency of heat waves, which negatively impacts agricultural fields. Despite numerous studies on heat stress responses and signal transduction in model plant species, the molecular mechanism underlying thermomorphogenesis in Panax ginseng remains largely unknown. Here, we investigated the high temperature response of ginseng at the phenotypic and molecular levels. Both the primary shoot growth and secondary root growth of ginseng plants were significantly reduced at high temperature. Histological analysis revealed that these decreases in shoot and root growth were caused by decreases in cell elongation and cambium stem cell activity, respectively. Analysis of P. ginseng RNA-seq data revealed that heat-stress-repressed stem and root growth is closely related to changes in photosynthesis, cell wall organization, cell wall loosening, and abscisic acid (ABA) and jasmonic acid (JA) signaling. Reduction in both the light and dark reactions of photosynthesis resulted in defects in starch granule development in the storage parenchymal cells of the main tap root. Thus, by combining bioinformatics and histological analyses, we show that high temperature signaling pathways are integrated with crucial biological processes that repress stem and root growth in ginseng, providing novel insight into the heat stress response mechanism of P. ginseng

The Chlamydomonas transcription factor MYB1 mediates lipid accumulation under nitrogen depletion

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Transgenic poplar for phytoremediation

Heavy metals such as cadmium (Cd) and lead (Pb) are released into the environment by mining, industry, and agriculture. Phytoremediation is a low-cost and environmentally-friendly technology to clean up polluted sites. For effective phytoremediation, plants that can tolerate high level of pollutants are necessary. To engineer plants with enhanced metal tolerance and accumulation properties, we searched for genes that can improve heavy metal resistance through yeast mutant screening and Arabidopsis cDNA library screening, and found ScYcf1, ScYHL035C, ScPdr13, and AtPcr1. ScYcf1 and ScYHL035C are multidrug resistance-associated protein (MRP) subfamily of ABC transporter. ScPdr1 is a heat shock protein 70(HSP70). AtPcr1 is a plant protein which enhances cadmium resistance by reducing Cd(II) in the cell. We expressed the genes in poplar, a species that grows fast to high biomass, important characters of plants for application of phytoremediation. To prevent pollen dissemination from the transgenic plants, we introduced the genes into non-flowering mutant poplar. We compared growth of the transgenic and wild type poplar plants in Cd- and Pb-containing media, and found that the transgenic poplars were highly improved in the heavy metal resistance. These results suggest that they are useful for phytoremediation of Cd- and Pb-contaminated soils.11Nsci