Generation of Cas9 transgenic zebrafish and their application in establishing an ERV-deficient animal model

Objectives

To investigate the effect of endogenous Cas9 on genome editing efficiency in transgenic zebrafish.

Results

Here we have constructed a transgenic zebrafish strain that can be screened by pigment deficiency. Compared with the traditional CRISPR injection method, the transgenic zebrafish can improve the efficiency of genome editing significantly. At the same time, we first observed that the phenotype of vertebral malformation in early embryonic development of zebrafish after ZFERV knockout.

Conclusions

The transgenic zebrafish with expressed Cas9, is more efficient in genome editing. And the results of ZFERV knockout indicated that ERV may affect the vertebral development by Notch1/Delta D signal pathway.

     

Chemical Constituents and Insecticidal Activities of Ajania fruticulosa Essential Oil

The insecticidal activity and chemical constituents of the essential oil from Ajania fruticulosa were investigated. Twelve constituents representing 91.0% of the essential oil were identified, and the main constituents were 1,8‐cineole ( 41.40% ), (+)‐camphor ( 32.10% ), and myrtenol (8.15%). The essential oil exhibited contact toxicity against Tribolium castaneum and Liposcelis bostrychophila adults with LD₅₀ values of 105.67 μg/adult and 89.85 μg/cm², respectively. The essential oil also showed fumigant toxicity against two species of insect with LC₅₀ values of 11.52 and 0.65 mg/l, respectively. 1,8‐Cineole exhibited excellent fumigant toxicity (LC₅₀ = 5.47 mg/l) against T. castaneum. (+)‐Camphor showed obvious fumigant toxicity (LC₅₀ = 0.43 mg/l) against L. bostrychophila. Myrtenol showed contact toxicity (LD₅₀ = 29.40 μg/cm²) and fumigant toxicity (LC₅₀ = 0.50 mg/l) against L. bostrychophila. 1,8‐Cineole and (+)‐camphor showed strong insecticidal activity to some important insects, and they are main constituents of A. fruticulosa essential oil. The two compounds may be related to insecticidal activity of A. fruticulosa essential oil against T. castaneum and L. bostrychophila.     

Identification and mapping of <Emphasis Type="Italic">MLIW30</Emphasis>, a novel powdery mildew resistance gene derived from wild emmer wheat

Powdery mildew, caused by Blumeria graminis f.sp. tritici (Bgt), is a destructive foliar disease of common wheat in areas with cool or maritime climates. Wild emmer wheat, Triticum turgidum ssp. dicoccoides, the progenitor of both domesticated tetraploid durum wheat and hexaploid bread wheat, harbors abundant genetic diversity related to resistance to powdery mildew that can be utilized for wheat improvement. An F₂ segregating population was obtained from a cross between resistant bread wheat line 2L6 and susceptible cultivar Liaochun 10, after which genetic analysis of F₂ and F₂-derived F₃ families was performed by inoculating plants with isolate Bgt E09. The results of this experiment demonstrated that powdery mildew resistance in 2L6, which was derived from wild emmer wheat accession IW30, was controlled by a single dominant gene, temporarily designated MLIW30. Nineteen SSR markers and two STS markers linked with MLIW30 were acquired by applying bulked segregant analysis. Finally, MLIW30 was located to the long arm of chromosome 4A and found to be flanked by simple sequence repeat markers XB1g2000.2 and XB1g2020.2 at 0.1 cM. Because no powdery mildew resistance gene in or derived from wild emmer wheat has been reported in wheat chromosome 4A, MLIW30 might be a novel Pm gene.     

Development of a large number of SSR and InDel markers and construction of a high-density genetic map based on a RIL population of pepper (<Emphasis Type="Italic">Capsicum annuum</Emphasis> L.)

Capsicum annuum, the most widely cultivated species of pepper, is used worldwide for its important nutritional and medicinal values. The construction of an intraspecific high-density genetic linkage map would be of practical value for pepper breeding. However, the numbers of PCR-based simple sequence repeat (SSR) and insertion/deletion (InDel) markers that are available are limited, and there is a need to develop a saturated, intraspecific linkage map. The non-redundant Capsicum species’ expressed sequence tag (EST) database from the National Center for Biotechnology Information was used in this study to develop a total of 902 usable EST-SSR markers. Additionally, 177,587 SSR loci were identified based on the pepper genomic information, including 9182 SSR loci 500 bp both upstream and downstream of coding regions. Another 4497 stable and reliable InDel loci were also developed. From 9182 SSR and 4497 InDel loci, 3356 pairs of genomic SSR primers and 1400 pairs of InDel primers that were evenly distributed in 12 chromosomes were selected. A high-density intraspecific genetic map of C. annuum was constructed using the F₁₀-generation recombinant inbred line of parents PM702 and FS871 as the mapping population, screening the selected 3356 pairs of genomic SSR primers and 1400 pairs of InDel primers and the 902 EST-SSR markers developed earlier, and 524 published SSR markers and 299 orthologous markers (including 263 COSII markers and 36 tomato-derived markers) used previously to develop an interspecific genetic map (C. annuum × C. frutescens). Eventually, a high-density complete genetic intraspecific linkage map of C. annuum containing 12 linkage groups and 708 molecular markers with a length of 1260.00 cM and an average map distance of 1.78 cM was produced. This intraspecific, high-density, complete genetic linkage map of C. annuum contains the largest number of SSR and InDel markers and the highest amount of saturation so far, and it will be of considerable significance for the breeding of improved cultivars of this important field crop in the future.     

Normalization of TAM post-receptor signaling reveals a cell invasive signature for Axl tyrosine kinase

Background

Tyro3, Axl, and Mertk (TAMs) are a family of three conserved receptor tyrosine kinases that have pleiotropic roles in innate immunity and homeostasis and when overexpressed in cancer cells can drive tumorigenesis.

Methods

In the present study, we engineered EGFR/TAM chimeric receptors (EGFR/Tyro3, EGFR/Axl, and EGF/Mertk) with the goals to interrogate post-receptor functions of TAMs, and query whether TAMs have unique or overlapping post-receptor activation profiles. Stable expression of EGFR/TAMs in EGFR-deficient CHO cells afforded robust EGF inducible TAM receptor phosphorylation and activation of downstream signaling.

Results

Using a series of unbiased screening approaches, that include kinome-view analysis, phosphor-arrays, RNAseq/GSEA analysis, as well as cell biological and in vivo readouts, we provide evidence that each TAM has unique post-receptor signaling platforms and identify an intrinsic role for Axl that impinges on cell motility and invasion compared to Tyro3 and Mertk.

Conclusion

These studies demonstrate that TAM show unique post-receptor signatures that impinge on distinct gene expression profiles and tumorigenic outcomes.

     

Comparative Epidemiology of Human Infections with Middle East Respiratory Syndrome and Severe Acute Respiratory Syndrome Coronaviruses among Healthcare Personnel

The largest nosocomial outbreak of Middle East respiratory syndrome (MERS) occurred in South Korea in 2015. Health Care Personnel (HCP) are at high risk of acquiring MERS-Coronavirus (MERS-CoV) infections, similar to the severe acute respiratory syndrome (SARS)-Coronavirus (SARS-CoV) infections first identified in 2003. This study described the similarities and differences in epidemiological and clinical characteristics of 183 confirmed global MERS cases and 98 SARS cases in Taiwan associated with HCP. The epidemiological findings showed that the mean age of MERS-HCP and total MERS cases were 40 (24~74) and 49 (2~90) years, respectively, much older than those in SARS [SARS-HCP: 35 (21~68) years, p = 0.006; total SARS: 42 (0~94) years, p = 0.0002]. The case fatality rates (CFR) was much lower in MERS-HCP [7.03% (9/128)] or SARS-HCP [12.24% (12/98)] than the MERS-non-HCP [36.96% (34/92), p<0.001] or SARS-non-HCP [24.50% (61/249), p<0.001], however, no difference was found between MERS-HCP and SARS-HCP [p = 0.181]. In terms of clinical period, the days from onset to death [13 (4~17) vs 14.5 (0~52), p = 0.045] and to discharge [11 (5~24) vs 24 (0~74), p = 0.010] and be hospitalized days [9.5 (3~22) vs 22 (0~69), p = 0.040] were much shorter in MERS-HCP than SARS-HCP. Similarly, days from onset to confirmation were shorter in MERS-HCP than MERS-non-HCP [6 (1~14) vs 10 (1~21), p = 0.044]. In conclusion, the severity of MERS-HCP and SARS-HCP was lower than that of MERS-non-HCP and SARS-non-HCP due to younger age and early confirmation in HCP groups. However, no statistical difference was found in MERS-HCP and SARS-HCP. Thus, prevention of nosocomial infections involving both novel Coronavirus is crucially important to protect HCP.     

Benefits of Biochar for Improving Ion Contents,Cell Membrane Permeability,Leaf Water Status and Yield of Rice Under Saline–Sodic Paddy Field Condition

Journal of Plant Growth Regulation - Saline–sodic is one of the major conditions threatening crop production. Biochar application could alleviate the adverse impacts of saline–sodic...