Development and Characterization of EST-SSR Markers From RNA-Seq Data in Phyllostachys violascens

Bamboo are woody grass species containing important economic and ecological values. Lei bamboo (Phyllostachys violascens) is a kind of shoot-producing bamboo species with the highest economic yield per unit area. However, identifying different varieties of Lei bamboo based on morphological characteristics is difficult. Microsatellites play an important role in plant identification and genetic diversity analysis and are superior to other molecular markers. In this study, we identified 18,356 expressed sequence tag-simple sequence repeat (EST-SSR) loci in Lei bamboo transcriptome data. A total of 11,264 primer pairs were successfully designed from unigenes of all EST-SSR loci, and 96 primer pairs were randomly selected and synthesized. A total of 54 primer pairs were used for classifying 16 Lei bamboo varieties and 10 different Phyllostachys species. The number of polymorphism alleles among the 54 primer pairs ranged from 3 to 12 for P. violascens varieties and 3 to 20 for Phyllostachys. The phylogenetic tree based on polymorphism alleles successfully distinguished 16 P. violascens varieties and 10 Phyllostachys species. Our study provides abundant EST-SSR resources that are useful for genetic diversity analysis and molecular verification of bamboo and suggests that SSR markers developed from Lei bamboo are more efficient and reliable than ISSR, SRAP or AFLP markers

Homo- and Hetero-Dimers of CAD Enzymes Regulate Lignification and Abiotic Stress Response in Moso Bamboo

Lignin biosynthesis enzymes form complexes for metabolic channelling during lignification and these enzymes also play an essential role in biotic and abiotic stress response. Cinnamyl alcohol dehydrogenase (CAD) is a vital enzyme that catalyses the reduction of aldehydes to alcohols, which is the final step in the lignin biosynthesis pathway. In the present study, we identified 49 CAD enzymes in five Bambusoideae species and analysed their phylogenetic relationships and conserved domains. Expression analysis of Moso bamboo PheCAD genes in several developmental tissues and stages revealed that among the PheCAD genes, PheCAD2 has the highest expression level and is expressed in many tissues and PheCAD1, PheCAD6, PheCAD8 and PheCAD12 were also expressed in most of the tissues studied. Co-expression analysis identified that the PheCAD2 positively correlates with most lignin biosynthesis enzymes, indicating that PheCAD2 might be the key enzyme involved in lignin biosynthesis. Further, more than 35% of the co-expressed genes with PheCADs were involved in biotic or abiotic stress responses. Abiotic stress transcriptomic data (SA, ABA, drought, and salt) analysis identified that PheCAD2, PheCAD3 and PheCAD5 genes were highly upregulated, confirming their involvement in abiotic stress response. Through yeast two-hybrid analysis, we found that PheCAD1, PheCAD2 and PheCAD8 form homo-dimers. Interestingly, BiFC and pull-down experiments identified that these enzymes form both homo- and hetero- dimers. These data suggest that PheCAD genes are involved in abiotic stress response and PheCAD2 might be a key lignin biosynthesis pathway enzyme. Moreover, this is the first report to show that three PheCAD enzymes form complexes and that the formation of PheCAD homo- and hetero- dimers might be tissue specific

Motion of phase boundary during antiferroelectric–ferroelectric transition in a PbZrO3-based ceramic

The in situ biasing transmission electron microscopy technique is employed to investigate the nucleation and growth of the ferroelectric phase during the electric field-induced phase transition in Pb0.99{Nb0.02[(Zr0.57Sn0.43)0.94Ti0.06]0.98}O3, a PbZrO3-based antiferroelectric ceramic. The first-order displacive phase transition is found to be highly reversible with the initial antiferroelectric domain configuration almost completely recovered upon removal of the applied field. In the forward transition from the antiferroelectric to ferroelectric phase, {100}c facets are dominant on the phase boundary; while in the reverse transition from the ferroelectric to antiferroelectric phase during bias unloading, the phase boundary is segmented into {101}c and {121}c facets. The motion of the phase boundary is nonuniform, taking the form of sequential sweeping of facet segments. The elastic distortion energy and the depolarization energy at the antiferroelectric/ferroelectric phase boundary is suggested to dictate the facet motion

Homo- and Hetero-Dimers of CAD Enzymes Regulate Lignification and Abiotic Stress Response in Moso Bamboo

Lignin biosynthesis enzymes form complexes for metabolic channelling during lignification and these enzymes also play an essential role in biotic and abiotic stress response. Cinnamyl alcohol dehydrogenase (CAD) is a vital enzyme that catalyses the reduction of aldehydes to alcohols, which is the final step in the lignin biosynthesis pathway. In the present study, we identified 49 CAD enzymes in five Bambusoideae species and analysed their phylogenetic relationships and conserved domains. Expression analysis of Moso bamboo PheCAD genes in several developmental tissues and stages revealed that among the PheCAD genes, PheCAD2 has the highest expression level and is expressed in many tissues and PheCAD1, PheCAD6, PheCAD8 and PheCAD12 were also expressed in most of the tissues studied. Co-expression analysis identified that the PheCAD2 positively correlates with most lignin biosynthesis enzymes, indicating that PheCAD2 might be the key enzyme involved in lignin biosynthesis. Further, more than 35% of the co-expressed genes with PheCADs were involved in biotic or abiotic stress responses. Abiotic stress transcriptomic data (SA, ABA, drought, and salt) analysis identified that PheCAD2, PheCAD3 and PheCAD5 genes were highly upregulated, confirming their involvement in abiotic stress response. Through yeast two-hybrid analysis, we found that PheCAD1, PheCAD2 and PheCAD8 form homo-dimers. Interestingly, BiFC and pull-down experiments identified that these enzymes form both homo- and hetero- dimers. These data suggest that PheCAD genes are involved in abiotic stress response and PheCAD2 might be a key lignin biosynthesis pathway enzyme. Moreover, this is the first report to show that three PheCAD enzymes form complexes and that the formation of PheCAD homo- and hetero- dimers might be tissue specific

Lung-derived macrophage migration inhibitory factor in adult patients with septic shock, and its role in cardiocirculatory depression

Migration inhibitory factor (MIF), a critical proinflammatory mediator in sepsis, has a profound affect on cardiovascular function. Our animal studies show that the lungs release MIF into the systemic circulation during late sepsis. MIF released in this way has direct and immediate access to cardiac cells. The purpose of our study was to assess the lung as a source of MIF in human septic shock patients and to further study the MIF-associated pathways involved in cardiovascular depression

Gremlin1 Delivered by Mesenchymal Stromal Cells Promoted Epithelial-Mesenchymal Transition in Human Esophageal Squamous Cell Carcinoma

Backgroud/Aims: Mesenchymal stromal cells (MSCs) are a major component of the tumor microenvironment (TME). Several studies focusing on tumor-derived MSCs have demonstrated that they exhibit a strong ability to promote the tumor epithelial-mesenchymal transition (EMT). However, the factors mediating these effects are poorly understood. Methods: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry assays were used to detect the expression of Gremlin1 (GREM1) in human esophageal squamous cell carcinoma (ESCC) tissues. ShRNA silencing, flow cytometry, cell counting kit (CCK8) assay, invasion assay, western blot were used to detect the effect of GREM1 in ECa109, TE-1 cell lines and xenograft tumor models. Results: In the current study, we found that the GREM1 was overexpressed in human ESCC tissues. The conditioned medium from mesenchymal stromal cells (MSCs-CM) enhanced the malignancy of xenograft esophageal tumors in vivo, as well as the cell proliferation, viability and invasion of the esophageal carcinoma cell lines ECa109 and TE-1 in vitro. Furthermore, the shRNA silencing of GREM1 in MSCs (shGREM1-MSCs) reversed the increased malignancy of the esophageal tumor in vivo, while the conditioned medium from shGREM1-MSCs (shGREM1-MSCs-CM) affected the cell cycle and cell invasion in vitro. These processes were accompanied by the EMT in the ECa109 and TE-1 cell lines with an alteration in the expression levels of mesenchymal and epithelial markers. Furthermore, the TGF-β/BMP (transforming growth factor-beta/bone morphogenetic protein) signaling pathway participated in the shGREM1-MSCs-CM-induced anti-tumor effect on enhanced esophageal malignancy induced by MSCs-CM treatment. Conclusions: Taken together, our study suggested that GREM1 delivered by MSCs promoted EMT in ESCC in vitro and in vivo, which is partly through TGF-β/BMP signaling pathway. The results provide experimental evidence to a potential therapeutic target in the treatment of esophageal cancer

Role of HMGB1 in apoptosis-mediated sepsis lethality

Severe sepsis, a lethal syndrome after infection or injury, is the third leading cause of mortality in the United States. The pathogenesis of severe sepsis is characterized by organ damage and accumulation of apoptotic lymphocytes in the spleen, thymus, and other organs. To examine the potential causal relationships of apoptosis to organ damage, we administered Z-VAD-FMK, a broad-spectrum caspase inhibitor, to mice with sepsis. We found that Z-VAD-FMK–treated septic mice had decreased levels of high mobility group box 1 (HMGB1), a critical cytokine mediator of organ damage in severe sepsis, and suppressed apoptosis in the spleen and thymus. In vitro, apoptotic cells activate macrophages to release HMGB1. Monoclonal antibodies against HMGB1 conferred protection against organ damage but did not prevent the accumulation of apoptotic cells in the spleen. Thus, our data indicate that HMGB1 production is downstream of apoptosis on the final common pathway to organ damage in severe sepsis

A concentration-dependent endocytic trap and sink mechanism converts Bmper from an activator to an inhibitor of Bmp signaling

Bmper, which is orthologous to Drosophila melanogaster crossveinless 2, is a secreted factor that regulates Bmp activity in a tissue- and stage-dependent manner. Both pro- and anti-Bmp activities have been postulated for Bmper, although the molecular mechanisms through which Bmper affects Bmp signaling are unclear. In this paper, we demonstrate that as molar concentrations of Bmper exceed Bmp4, Bmper dynamically switches from an activator to an inhibitor of Bmp4 signaling. Inhibition of Bmp4 through a novel endocytic trap-and-sink mechanism leads to the efficient degradation of Bmper and Bmp4 by the lysosome. Bmper-mediated internalization of Bmp4 reduces the duration and magnitude of Bmp4-dependent Smad signaling. We also determined that Noggin and Gremlin, but not Chordin, trigger endocytosis of Bmps. This endocytic transport pathway expands the extracellular roles of selective Bmp modulators to include intracellular regulation. This dosage-dependent molecular switch resolves discordances among studies that examine how Bmper regulates Bmp activity and has broad implications for Bmp signal regulation by secreted mediators