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Multilocus genomic data sets can be used to infer a rich set of information about the evolutionary history of a lineage, including gene trees, species trees, and phylogenetic networks. However, user‐friendly tools to run such integrated analyses are lacking, and workflows often require tedious reformatting and handling time to shepherd data through a series of individual programs. Here, we present a tool written in Python—TREEasy—that performs automated sequence alignment (with MAFFT), gene tree inference (with IQ‐Tree), species inference from concatenated data (with IQ‐Tree and RaxML‐NG), species tree inference from gene trees (with ASTRAL, MP‐EST, and STELLS2), and phylogenetic network inference (with SNaQ and PhyloNet). The tool only requires FASTA files and nine parameters as inputs. The tool can be run as command line or through a Graphical User Interface (GUI). As examples, we reproduced a recent analysis of staghorn coral evolution, and performed a new analysis on the evolution of the “WGD clade” of yeast. The latter revealed novel patterns that were not identified by previous analyses. TREEasy represents a reliable and simple tool to accelerate research in systematic biology ( https://github.com/MaoYafei/TREEasy ).  相似文献   
995.
Gammaretroviral and lentiviral vectors (γ‐RV and LV) are among the most used vectors in gene therapy. Currently, human embryonic kidney (HEK) 293 cells, the manufacture platform of choice for these vectors, provide low transducing particle yields, challenging their therapeutic applications and commercialization. This work studies metabolic pathways, focusing on endoplasmic reticulum (ER) protein processing and anti‐apoptotic mechanisms, influencing vector productivity in HEK 293 cell substrates. To that end, four candidate genes—protein disulfide isomerase family A member 2 gene, heat shock protein family A (Hsp70) member 5 gene, X‐box binding protein 1 gene (ER protein processing), and B‐cell lymphoma 2 protein gene (anti‐apoptotic)—are individually stably expressed in the cells. How their overexpression level influence vector yields is analyzed by establishing cell populations with incremental genomic copies of each. γ‐RV volumetric productivity increases up to 97% when overexpressing ER protein processing genes. LV volumetric production increases 53% when overexpressing the anti‐apoptotic gene. Improvements are associated with higher cell specific productivities and dependent on gene overexpression level, highlighting the importance of fine‐tuning gene expression. Overall, this work discloses gene engineering targets enabling efficient gene therapy product manufacture showing that ER protein processing and anti‐apoptotic pathways are pivotal to producer cell performance.  相似文献   
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Disease resistance (R) gene, RPP13, plays an important role in the resistance of plants to pathogen infections; its function in resistance of wheat to powdery mildew remains unknown. In this study, a RNA-Seq technique was used to monitor expression of genes in susceptible wheat ‘Jing411’ and resistant near-isogenic line ‘BJ-1’ in response to powdery mildew infection. Overall, 413 differential expression genes were observed and identified as involved in disease resistance. RPP13 homologous gene on wheat chromosome 7D was preliminarily identified using the wheat 660K SNP chip. RPP13 was highly expressed in ‘BJ-1’ and encodes 1,027 amino acids, including CC, NB and LRR domain, termed TaRPP13-3. After inoculation with powdery mildew, expression of TaRPP13-3 in resistant wheat changed with time, but average expression was higher when compared to susceptible variety, thus indicating that TaRPP13-3 is involved in resistance to powdery mildew. Virus-induced gene silencing (VIGS) was used to inhibit expression of TaRPP13-3 in resistant parent ‘Brock’. Results indicated that silencing of TaRPP13-3 led to decreased disease resistance in ‘Brock’. Overall results of this study indicate that TaRPP13-3 gene is involved in the defence response of wheat to powdery mildew and plays a positive role in wheat powdery mildew interactions.  相似文献   
998.
Membrane trafficking plays a crucial role in cell polarity by directing lipids and proteins to specific subcellular locations in the cell and sustaining a polarized state. The Golgi apparatus, the master organizer of membrane trafficking, can be subdivided into three layers that play different mechanical roles: a cytoskeletal layer, the so-called Golgi matrix, and the Golgi membranes. First, the outer regions of the Golgi apparatus interact with cytoskeletal elements, mainly actin and microtubules, which shape, position, and orient the organelle. Closer to the Golgi membranes, a matrix of long coiled–coiled proteins not only selectively captures transport intermediates but also participates in signaling events during polarization of membrane trafficking. Finally, the Golgi membranes themselves serve as active signaling platforms during cell polarity events. We review here the recent findings that link the Golgi apparatus to cell polarity, focusing on the roles of the cytoskeleton, the Golgi matrix, and the Golgi membranes.  相似文献   
999.
Specificity is a crucial condition that hampers the application of non-viral vectors for cancer gene therapy. In a previous study, we developed an efficient gene vector, stearyl-CAMEL, using N-terminal stearylation of the antimicrobial peptide CAMEL. Substance P (SP), an 11-residue neuropeptide, rapidly enters cells after binding to the neurokinin-1 receptor (NK1R), which is expressed in many cancer cell lines. In this study, the NK1R-targeted gene vector stearyl-CMSP was constructed by conjugating SP to the C-terminus of stearyl-CAMEL. Our results indicated that stearyl-CMSP displayed significant transfection specificity for NK1R-expressing cells compared with that shown by stearyl-CAMEL. Accordingly, the stearyl-CMSP/p53 plasmid complexes had significantly higher antiproliferative activity against HEK293-NK1R cells than they did against HEK293 cells, while the stearyl-CAMEL/p53 plasmid complexes did not show this specificity in antiproliferative activity. Consequently, conjugation of the NK1R-targeted ligand SP is a simple and successful strategy to construct efficient cancer-targeted non-viral gene vectors.  相似文献   
1000.
Chimonanthus salicifolius, a member of the Calycanthaceae of magnoliids, is one of the most famous medicinal plants in Eastern China. Here, we report a chromosome‐level genome assembly of Csalicifolius, comprising 820.1 Mb of genomic sequence with a contig N50 of 2.3 Mb and containing 36 651 annotated protein‐coding genes. Phylogenetic analyses revealed that magnoliids were sister to the eudicots. Two rounds of ancient whole‐genome duplication were inferred in the Csalicifolious genome. One is shared by Calycanthaceae after its divergence with Lauraceae, and the other is in the ancestry of Magnoliales and Laurales. Notably, long genes with > 20 kb in length were much more prevalent in the magnoliid genomes compared with other angiosperms, which could be caused by the length expansion of introns inserted by transposon elements. Homologous genes within the flavonoid pathway for Csalicifolius were identified, and correlation of the gene expression and the contents of flavonoid metabolites revealed potential critical genes involved in flavonoids biosynthesis. This study not only provides an additional whole‐genome sequence from the magnoliids, but also opens the door to functional genomic research and molecular breeding of Csalicifolius.  相似文献   
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