Mining of disease-resistance genes in Crocus sativus based on transcriptome sequencing

Introduction:Crocus sativus L. has an important medicinal and economic value in traditional perennial Chinese medicine. However, due to its unique growth characteristics, during cultivation it is highly susceptible to disease. The absence of effective resistance genes restricts us to breed new resistant varieties of C. sativus.Methods: In present study, comprehensive transcriptome sequencing was introduced to explore the disease resistance of the candidate gene in healthy and corm rot-infected C. sativus.Results and discussion: Totally, 43.72 Gb of clean data was obtained from the assembly to generate 65,337 unigenes. By comparing the gene expression levels, 7,575 differentially expressed genes (DEGs) were primarily screened. A majority of the DEGs were completely in charge of defense and metabolism, and 152 of them were annotated as pathogen recognition genes (PRGs) based on the PGRdb dataset. The expression of some transcription factors including NAC, MYB, and WRKY members, changed significantly based on the dataset of transcriptome sequencing. Therefore, this study provides us some valuable information for exploring candidate genes involved in the disease resistance in C. sativus

Beyond the pandemic : COVID-19 pandemic changed the face of life

Funding Information: This work was supported by the Swedish Research Council Vetenskapsr?det (VR grant 2016?05885). Funding Information: Acknowledgments: H.R. El-Seedi is very grateful to the Swedish Research links grant VR 2016– 05885 and the Department of Molecular Biosciences, Wenner-Grens Institute, Stockholm University, Sweden, for the financial support. Publisher Copyright: © 2021 by the au-thors. Licensee MDPI, Basel, Switzerland.The COVID-19 pandemic is a serious challenge for societies around the globe as entire populations have fallen victim to the infectious spread and have taken up social distancing. In many countries, people have had to self-isolate and to be confined to their homes for several weeks to months to prevent the spread of the virus. Social distancing measures have had both negative and positive impacts on various aspects of economies, lifestyles, education, transportation, food supply, health, social life, and mental wellbeing. On other hands, due to reduced population movements and the decline in human activities, gas emissions decreased and the ozone layer improved; this had a positive impact on Earth’s weather and environment. Overall, the COVID-19 pandemic has negative effects on human activities and positive impacts on nature. This study discusses the impact of the COVID-19 pandemic on different life aspects including the economy, social life, health, education, and the environment.publishersversionPeer reviewe

Characterization and phylogenetic analysis of the complete chloroplast genome of Ophiorrhiza pumila (Rubiaceae)

Ophiorrhiza pumila (Rubiaceae) is an herbaceous plant that grows streamside in forest gullies or wetlands in the shade. Complete chloroplast genome of O. pumila was obtained and analyzed its phylogeny relationship within Rubiaceae plants. The results showed that the genome had a typical quadripartite structure of 154,385 bp, and contained a total of 112 unique genes, including 79 protein-coding genes, 29 tRNA genes, and 4 rRNA genes. Phylogenetic analysis suggested that O. pumila is sister to a highly supported clade composed of 10 species including Morinda officinalis, Gynochthodes cochinchinensis, Saprosma merrillii, Hedyotis ovata, Foonchewia guangdongensis, Dunnia sinensis, Paederia scandens, Leptodermis scabrida, Rubia cordifolia, and Galium mollugo. The complete chloroplast genome provides valuable information for the phylogenetic analysis of O. pumila

Transcription Factor SmWRKY1 Positively Promotes the Biosynthesis of Tanshinones in Salvia miltiorrhiza

Tanshinones, one group of bioactive diterpenes, were widely used in the treatment of cardiovascular diseases. WRKYs play important roles in plant metabolism, but their regulation mechanism in Salvia miltiorrhiza remains elusive. In this study, one WRKY transcription factor SmWRKY1 was isolated and functionally characterized from S. miltiorrhiza. Multiple sequence alignment and phylogenetic tree analysis showed SmWRKY1 shared high homology with other plant WRKYs such as CrWRKY1. SmWRKY1 was found predominantly expressed in leaves and stems, and was responsive to salicylic acid (SA), methyl jasmonate (MeJA), and nitric oxide (NO) treatment. Subcellular localization analysis found that SmWRKY1 was localized in the nucleus. Over-expression of SmWRKY1 significantly elevated the transcripts of genes coding for enzymes in the MEP pathway especially 1-deoxy-D-xylulose-5-phosphate synthase (SmDXS) and 1-deoxy-D-xylulose-5-phosphate reductoisomerase (SmDXR), resulted in over fivefold increase in tanshinones production in transgenic lines (up to 13.7 mg/g DW) compared with the control lines. A dual-luciferase (Dual-LUC) assay showed that SmWRKY1 can positively regulate SmDXR expression by binding to its promoter. Our work revealed that SmWRKY1 participated in the regulation of tanshinones biosynthesis and acted as a positive regulator through activating SmDXR in the MEP pathway, thus provided a new insight to further explore the regulation mechanism of tanshinones biosynthesis

Application progress of DNA molecular markers in non-heading Chinese cabbage genetic breeding

This paper reviews the classification and characteristics of DNA molecular markers in non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) genetic breeding,and its application in genetics diversity analysis,genetic map construction,quantitative trait locus (QTLs) mapping and molecular marker-assisted selection. Finally,some limitations of DNA molecular markers on genetic improvement and assistant breeding of non-heading Chinese cabbage are pointed out,and some suggestions are put forward,aiming to provide valuable information for genetic breeding of non-heading Chinese cabbage

Morphological character and RAPD analysis of genetic diversity of different types of <i>Brassica campestris</i> L. ssp. <i>chinensis</i> (L.) Makino var. <i>communis</i> Tsee et Lee.pakchoi

The genetic diversity of 24 accessions of pakchoi(Brassica campestris L. ssp. chinensis (L.) Makino var. communis Tsee et Lee.) from different districts of China was identified by morphological characters and RAPD analysis.The results showed that the coefficient of variation of 13 morphological characters of materials was from 12.4% to 69.9%,the most was petiole length,and the least cotyledon.24 accessions were clustered into 4 groups at the distance of 5 in morphological cluster.113 bands were detecteded by15 RAPD primers,and 83 were polymorphic.The percentage of polymorphic bands was 73.4%,and the number of average and polymorphic bands each primer were 7.53 and 5.53 respectively.In RAPD analysis,8 groups at the genetic distance of 0.77 were obtained based on RAPD data.There were the overlaps and segmentation between the results of RAPD and morphological cluster.Nei′s diversity (H)and Shannon information index (I) based on 4 types of morphological analysis were both the order of Ⅳ>Ⅰ>Ⅲ>Ⅱ,and H and I of Ⅳ were 0.2395 and 0.3523 respectively.H and I of Jianghui area were the highest in China,being 0.2076 and 0.3098 respectively.These data were in accordance with the diversity characteristics and rejoin distribution of pakchoi germplasms

Study on plantlet regeneration and <i>in vitro</i> culture of non-heading Chinese cabbage

The cotyledon of non-heading Chinese cabbage(Brassica campestris ssp.chinensis Makino)was used as explants to investigate the effects of different concentrations of hormone and of AgNO3 on its culture in vitro based on one variety ″short broom suzhouqing″.The results showed that the induction rate of adventitious bud was the highest on the MS medium containing 0.3 mg/L NAA and 5 mg/L 6-BA,while 5 mg/L AgNO3 added on this medium could efficiently improve the regeneration rate (high to 31.3%).Meanwhile,half strength MS supplemented with 0.3 mg/L NAA was the best medium for rooting of non-heading Chinese cabbage.Our study set up a primary regeneration system for non-heading Chinese cabbage short broom suzhouqing.This system laid the foundation of molecular breeding of non-heading Chinese cabbage using genetic engineering further

Genome-Wide Identification and Characterization of the <i>Salvia miltiorrhiza</i> Histone Deacetylase (HDAC) Family in Response to Multiple Abiotic Stresses

Salvia miltiorrhiza is a plant commonly used in traditional Chinese medicine. Its material bases for treating diseases are tanshinones and phenolic acids, including salvianolic acids. Histone deacetylase proteins (HDACs) are a class of specific functional enzymes that interact with acetylation groups on the N-terminal lysine of histone proteins further regulate gene transcription through structural changes at the chromatin level. HDACs involved in the growth and development of various plants, and induced by plant hormones to regulate the internal environment of plants to resist stress, at the same time affect the accumulation of some secondary metabolites. However, the role of SmHDACs on the accumulation of salvianolic acid in S. miltiorrhiza remains unclear. In this study, 16 SmHDACs genes were identified from the high-quality S. miltiorrhiza genome, their physicochemical properties were predicted. In phylogenetic trees co-constructed with HDACs proteins from other plants, SmHDACs was divided into three subfamilies, each with similar motif and conserved domain composition. The distribution of the three subfamilies is similar to that of dicotyledonous plants. Chromosome localization analysis showed that SmHDACs genes were randomly located. Cis-acting element analysis predicted that SmHDACs gene expression may be related to and induced by various phytohormones, such as MeJA and ABA. By combining the expression pattern and co-expression network induced by phytohormones, we speculate that SmHDACs may further influence the synthesis of salvianolic acid, and identified SmHDA5, a potential functional gene, then speculate its downstream target based on the co-expression network. In summary, we analyzed the SmHDACs gene family of S. miltiorrhiza and screened out the potential functional gene SmHDA5. From the perspective of epigenetics, we proposed the molecular mechanism of plant hormone promoting salvianolic acid synthesis, which filled the gap in the subdivision of histone deacetylase in S. miltiorrhiza research, provided a theoretical basis for the culture and transformation of S. miltiorrhiza germplasm resources