Biology subjects

Wu, Q.

Publications and source records attributed to Wu, Q..

27 records · Page 2Linked to original sources

bioRxiv2018

Comparative Transcriptomic and Metabolomic Analyses in Response to Cold in Tartary Buckwheat (Fagopyrum tataricum)

Plants recognize multiple environmental signals that lead to substantial changes in the regulation of primary and secondary metabolism in order to adapt to environmental stresses. In this study, we investigate the effects of cold on the metabolome and transcriptome of tartary buckwheat, focusing on the phenylpropanoid biosynthetic pathway. Using RNA-sequencing analysis of the cold-regulated transcriptome of buckwheat, we identified several phenylpropanoid biosynthetic transcripts that accumulated in response to cold. To confirm the transcriptome data, we analyzed the expression of the phenylpropanoid biosynthetic transcripts in cold-treated buckwheat and showed that all the phenylpropanoid biosynthetic transcripts were upregulated in coldtreated buckwheat seedlings with the exception of FtDFR. From the metabolic profiling based on the GC-TOF-MS analysis, we show that most of the sugars and their derivatives significantly increase in response to cold, while some of amino acids and their derivatives decrease in cold-treated plants. Some organic acids derived from the tricarboxylic acid (TCA) cycle increased in the cold-treated plants compared with in the plants grown at 25{degrees}C. In particular, the contents of anthocyanins and proanthocyanidins were significantly increased by cold treatment. In summary, these results indicate that the metabolome and transcriptome of tartary buckwheat are extensively affected by cold stresses.\n\nHighlightUsing the RNA-sequencing data and the metabolic profiling analysis, we identified the changes that occur in the transcriptome and metabolome of tartary buckwheat in response to cold, focusing on the flavonoid biosynthetic pathway.\n\nAbbreviations

systems biology↗

bioRxiv2018

GITAR: An open source tool for analysis and visualization of Hi-C data

Interactions between chromatin segments play a large role in functional genomic assays and developments in genomic interaction detection methods have shown interacting topological domains within the genome. Among these methods, Hi-C plays a key role. Here, we present GITAR (Genome Interaction Tools and Resources), a software to perform a comprehensive Hi-C data analysis, including data preprocessing, normalization, visualization and topologically associated domains (TADs) analysis. GITAR is composed of two main modules: 1) HiCtool, a Python library to process and visualize Hi-C data, including TADs analysis and 2) Processed data library, a large collection of human and mouse datasets processed using HiCtool. HiCtool leads the user step-by-step through a pipeline which goes from the raw Hi-C data to the computation, visualization and optimized storage of intra-chromosomal contact matrices and topological domain coordinates. A large collection of standardized processed data allows to compare different datasets in a consistent way and it saves time of work to obtain data for visualization or additional analyses. GITAR enables users without any programming or bioinformatic expertise to work with Hi-C data and it is freely available for the public at http://genomegitar.org as an open source software.

bioinformatics↗

bioRxiv2017

Pyk2 suppresses contextual fear memory in a kinase-independent manner

Post-traumatic stress disorder (PTSD) is a psychological illness characterized by recalling a feeling of distress when re-experiencing the original trauma-related cues. This associative fear response plays an important role in some psychiatric disorders and elucidation of the underlying mechanisms is of great importance. Here, we constructed Pyk2 null mice and found that these mutant mice showed enhancement in contextual-fear memory, but no changes in auditory-cued and spatial-referenced learning and memory. Moreover, using kinase mutant mice, we observed that Pyk2 suppressed contextual fear memory in a kinase-independent pathway. Using high-throughput RNA sequencing, we found that immediate early genes (IEGs), such as Npas4, cFos, Zif268/Egr1, Arc, and Nr4a1, were enhanced in Pyk2 null mice. We further demonstrated that Pyk2 disruption affected pyramidal neuronal complexity and spine dynamics. Thus, we demonstrated that Pyk2 is a novel fear memory suppressor molecule and Pyk2 null mice provides a model for understanding fear-related disorders.

genetics↗

bioRxiv2017

The CLAVATA receptor FASCIATED EAR2 responds to different CLE peptides by signaling through different downstream effectors.

Meristems contain groups of indeterminate stem cells that are critical for organ initiation throughout plant development. The shoot apical meristem (SAM) maintains itself and initiates all shoot organs, such as leaves, floral organs and axillary branch meristems. Development and balanced proliferation of the SAM is regulated by a feedback loop between CLAVATA (CLV) and WUSCHEL (WUS) signaling. CLV signaling is initiated by secretion of the CLV3 peptide ligand, which is perceived directly or indirectly by a number of Leucine-Rich-Repeat (LRR) receptor-like kinases, including CLV1 and BARELY ANY MERISTEM (BAM) 1-3, and RECEPTOR-LIKE PROTEIN KINASE 2 (RPK2), as well as the receptor-like protein CLV2 in a complex with the CORYNE (CRN) pseudokinase. However, CLV2, and its maize ortholog FASCIATED EAR2 (FEA2) appear to function in signaling by several related CLV3/EMBRYO-SURROUNDING REGION (CLE) peptide ligands, including CLV3. Nevertheless, it remains unknown how CLV2 or FEA2 transmit specific signals from distinct CLE peptides. Here we show that FEA2 is involved in signaling from at least 2 distinct CLE peptides, ZmCLE7, a maize CLV3 ortholog, and ZmFON2-LIKE CLE PROTEIN1 (ZmFCP1), a newly identified CLE peptide functioning in SAM regulation. Signaling from these 2 different CLE peptides appears to be transmitted through 2 different candidate downstream effectors, COMPACT PLANT2 (CT2), the alpha subunit of the maize heterotrimeric G protein, and maize CRN. Our data provide a novel framework to understand how diverse signaling peptides can activate different downstream pathways through common receptor proteins.

plant biology↗

bioRxiv2017

In vivo relevance of intercellular calcium signaling in Drosophila wing development

Recently, organ-scale intercellular Ca2+ transients (ICTs) were reported in the Drosophila wing disc. However, the functional in vivo significance of ICTs remains largely unknown. Here we demonstrate the in vivo relevance of intercellular Ca2+ signaling and its impact on wing development. We report that Ca2+ signaling in vivo decreases as wing discs mature. Ca2+ signaling ex vivo responds to fly extract in a dose-dependent manner. This suggests ICTs occur in vivo due to chemical stimulus that varies in concentration during development. RNAi mediated inhibition of genes required for ICTs results in defects in the size, shape, and vein patterning of adult wings. It also leads to reduction or elimination of in vivo Ca2+ transients. Further, perturbations to the extracellular matrix along the basal side of the wing disc stimulates intercellular Ca2+ waves. This is the first identified chemically defined, non-wounding stimulus of ICTs. Together, these results point toward specific in vivo functions of intercellular Ca2+ signaling to mediate mechanical stress dissipation and ensure robust patterning during development.

developmental biology↗

bioRxiv2017

Predictive model identifies strategies to enhance TSP1-mediated apoptosis signaling

This study explores strategies to enhance thrombospondin-1 (TSP1) induced apoptosis in endothelial cells, an important function that contributes to TSP1s anti-angiogenic effect. We established a mathematical model of TSP1-mediated intracellular signaling via the CD36 receptor. This model was used to investigate the effects of several approaches to perturb the TSP1-CD36 signaling network. Model simulations predict the population-based response to strategies to enhance TSP1-mediated apoptosis, such as downregulating the apoptosis inhibitor XIAP and inhibiting phosphatase activity. The model also postulates a new mechanism of low dosage doxorubicin treatment in combination with TSP1 stimulation. Using computational analysis, we predict which cells will undergo apoptosis, based on the initial intracellular concentrations of particular signaling species. Overall, the modeling framework predicts molecular strategies that increase TSP1-mediated apoptosis, which is useful in many disease settings.

systems biology↗

bioRxiv2017

Precise And Predictable DNA Fragment Editing Reveals Principles Of Cas9-Mediated Nucleotide Insertion

DNA fragment editing (DFE) or chromosomal engineering including inversions, deletions, and duplications by Cas9 with paired sgRNAs are important to investigate structural genome variations and developmental gene regulation, but little is known about the underlying mechanisms. Here we report that debilitating CtIP, which is thought to function in NHEJ, enhances precise DNA fragment deletion. By analyzing the inserted nucleotides at the junctions of DNA fragment inversions, deletions, and duplications, we find that Cas9 cleaves the noncomplementary strand with a flexible profile upstream of the PAM site and rationally-designed Cas9 nucleases have distinct cleavage profiles. Finally, Cas9-mediated nucleotide insertions of DFE are nonrandom and are equal to the combined sequences upstream of both PAM sites with predicted frequencies. Thus, precise and predictable DFEs could be achieved by perturbing DNA repair genes and using appropriate PAM configurations. These findings have important applications regarding 3D chromatin folding and enhancer insulation during gene regulation.

genetics↗

bioRxiv2017

Molecular Mapping Of YrTZ2, A Stripe Rust Resistance Gene In Wild Emmer Accession TZ-2 And Its Comparative Analyses With Aegilops tauschii

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a devastating disease that can cause severe yield losses. Identification and utilization of stripe rust resistance genes are essential for effective breeding against the disease. Wild emmer accession TZ-2, originally collected from Mount Hermon, Israel, confers near-immunity resistance against several prevailing Pst races in China. A set of 200 F6:7 recombinant inbred lines (RILs) derived from a cross between susceptible durum wheat cultivar Langdon and TZ-2 was used for stripe rust evaluation. Genetic analysis indicated that the stripe rust resistance of TZ-2 to Pst race CYR34 was controlled by a single dominant gene, temporarily designated YrTZ2. Through bulked segregant analysis (BSA) and SSR mapping, YrTZ2 was located on chromosome arm 1BS and flanked by SSR markers Xwmc230 and Xgwm413 with genetic distance of 0.8 cM (distal) and 0.3 cM (proximal), respectively. By applying wheat 90K iSelect SNP genotyping assay, 11 polymorphic loci (consist of 250 SNP markers) closely linked with YrTZ2 were identified. YrTZ2 was further delimited into a 0.8 cM genetic interval between SNP marker IWB19368 and SSR marker Xgwm413, and co-segregated with SNP marker IWB28744 (attached with 28 SNP markers). Comparative genomics analyses revealed high level of collinearity between the YrTZ2 genomic region and the orthologous region of Aegilops tauschii 1DS. The genomic region between loci IWB19368 and IWB31649 harboring YrTZ2 is orthologous to a 24.5 Mb genomic region between AT1D0112 and AT1D0150, spanning 15 contigs on chromosome 1DS. The genetic and comparative maps of YrTZ2 provide framework for map-based cloning and marker-assisted selection (MAS) of YrTZ2.

plant biology↗

bioRxiv2017

Morphogen signalling patterns calcium waves in the Drosophila wing disc

Organ development is driven by a set of patterned inductive signals. However, how these signals are integrated to coordinate tissue patterning is still poorly understood. Calcium ions (Ca2+) are critical signaling components involved in signal integration and are regulated by a core Ca2+ signaling toolkit. Ca2+ signaling encodes a significant fraction of information in cells through both amplitude and frequency-dependent regulation of transcription factors and key regulatory enzymes. A range of intercellular Ca2+ transients, including coordinated oscillations, recently have been reported in Drosophila wing discs. In an accompanying paper, we show that impaired Ca2+ signaling impacts the final size and shape of the wing. Here, we discover specific spatiotemporal signatures of Ca2+ transients during wing disc development. To do so, we developed a new neural-network-based approach for registration of oscillatory signals in organs that frequently move during imaging, and a pipeline for spatiotemporal analysis of intercellular Ca2+ oscillations. As a specific test case, we further demonstrated that the morphogen pathway, Hedgehog, controls frequencies of Ca2+ oscillations uniformly in the tissue and is required for spatial patterning of oscillation amplitudes. Thus, the time-averaged dynamics of spontaneous intercellular Ca2+ transients reflect the morphogenetic signaling state of the tissue during development. This suggests a general mechanism of physiological signaling that provides a memory of morphogenetic patterns. Additionally, our study provides a powerful approach for registering and quantifying oscillatory dynamics in developing organs.

developmental biology↗