Co-infection with a wheat rhabdovirus causes a reduction inMal de Río Cuarto virustiter in its planthopper vector

2017 ◽  
Vol 108 (2) ◽  
pp. 232-240
Author(s):  
A.D. Dumón ◽  
E.B. Argüello Caro ◽  
M.F. Mattio ◽  
V. Alemandri ◽  
M. del Vas ◽  
...  

AbstractMal de Río Cuarto virus(MRCV,Fijivirus,Reoviridae) causes one of the most important diseases in maize (Zea maysL.) in Argentina and has been detected in mixed infections with a rhabdovirus closely related to Maize yellow striate virus. In nature both viruses are able to infect maize and several grasses including wheat, and are transmitted in a persistent propagative manner byDelphacodes kuscheliFennah (Hemiptera: Delphacidae). This work describes the interactions between MRCV and rhabdovirus within their natural vector and the consequences of such co-infection regarding virus transmission and symptom expression. First- and third-instarD. kuschelinymphs were fed on MRCV-infected wheat plants or MRCV-rhabdovirus-infected oat plants, and two latency periods were considered. Transmission efficiency and viral load of MRCV-transmitting and non-transmitting planthoppers were determined by real-time quantitative polymerase chain reaction analysis (RTqPCR). Vector transmission efficiency was related to treatments (life stages at acquisition and latency periods). Nevertheless, no correlation between transmission efficiency and type of inoculum used to infect insects with MRCV was found. Treatment by third-instar nymphs 17 days after Acquisition Access Period was the most efficient for MRCV transmission, regardless of the type of inoculum. Plants co-infected with MRCV and rhabdovirus showed the typical MRCV symptoms earlier than plants singly infected with MRCV. The transmitting planthoppers showed significantly higher MRCV titers than non-transmitting insects fed on single or mixed inocula, confirming that successful MRCV transmission is positively associated with viral accumulation in the insect. Furthermore, MRCV viral titers were higher in transmitting planthoppers that acquired this virus from a single inoculum than in those that acquired the virus from a mixed inoculum, indicating that the presence of the rhabdovirus somehow impaired MRCV replication and/or acquisition. This is the first study about interactions between MRCV and a rhabdovirus closely related to Maize yellow striate virus in this insect vector (D. kuscheli), and contributes to a better understanding of planthopper–virus interactions and their epidemiological implications.

2019 ◽  
Vol 75 (7) ◽  
pp. 1979-1985 ◽  
Author(s):  
Jing Li ◽  
Wan Zhao ◽  
Wei Wang ◽  
Lili Zhang ◽  
Feng Cui

2015 ◽  
Vol 105 (4) ◽  
pp. 550-554 ◽  
Author(s):  
Keiichiro Matsukura ◽  
Tomomi Towata ◽  
Kazuhiro Yoshida ◽  
Junichi Sakai ◽  
Mitsuru Okuda ◽  
...  

We investigated Southern rice black-streaked dwarf virus (SRBSDV) accumulation in a vector insect, the whitebacked planthopper (Sogatella furcifera), to elucidate the association of virus accumulation in the vector with virus transmission efficiency. Real-time quantitative reverse transcription polymerase chain reaction analysis confirmed that this virus is transmitted in a persistent-propagative manner. SRBSDV was successfully transmitted by S. furcifera males in which RNA accumulation of the capsid protein gene of SRBSDV was >103 in the whole body of S. furcifera, indicating that the threshold accumulation of the virus RNA for virus transmission is 103 in an S. furcifera male. The SRBSDV detection rate in the immigrant population of S. furcifera was high in 2011 (39.5%); however, most of the insects contained fewer than 103 RNAs of the capsid protein gene. This result indicates that the risk of SRBSDV epidemics could be estimated from the proportion of virus-transmissible S. furcifera (i.e., S. furcifera that contained more than 103 RNAs of the virus capsid protein gene) rather than the SRBSDV detection rate in S. furcifera.


2021 ◽  
pp. 1358863X2110354
Author(s):  
Saranya Rajendran ◽  
Lakshmikirupa Sundaresan ◽  
Geege Venkatachalam ◽  
Krithika Rajendran ◽  
Jyotirmaya Behera ◽  
...  

Endothelium-derived nitric oxide (NO) is a mediator of angiogenesis. However, NO-mediated regulation of vasculogenesis remains largely unknown. In the present study, we show that the inhibition of NO significantly attenuated endothelial migration, ring formation, and tube formation. The contribution of nitric oxide synthase (NOS) enzymes during early vasculogenesis was assessed by evaluating endothelial NOS (eNOS) and inducible NOS (iNOS) mRNA expression during HH10–HH13 stages of chick embryo development. iNOS but not eNOS was expressed at HH12 and HH13 stages. We hypothesized that vasculogenic events are controlled by NOS-independent reduction of nitrite to NO under hypoxia during the very early phases of development. Semi-quantitative polymerase chain reaction analysis of hypoxia-inducible factor-1α (HIF-1α) showed higher expression at HH10 stage, after which a decrease was observed. This observation was in correlation with the nitrite reductase (NR) activity at HH10 stage. We observed a sodium nitrite-induced increase in NO levels at HH10, reaching a gradual decrease at HH13. The possible involvement of a HIF/NF-κB/iNOS signaling pathway in the process of early vasculogenesis is suggested by the inverse relationship observed between nitrite reduction and NOS activation between HH10 and HH13 stages. Further, we detected that NR-mediated NO production was inhibited by several NR inhibitors at the HH10 stage, whereas the inhibitors eventually became less effective at later stages. These findings suggest that the temporal dynamics of the NO source switches from NR to NOS in the extraembryonic area vasculosa, where both nitrite reduction and NOS activity are defined by hypoxia.


Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 177 ◽  
Author(s):  
Tereza Magalhaes ◽  
Alexis Robison ◽  
Michael Young ◽  
William Black ◽  
Brian Foy ◽  
...  

In urban settings, chikungunya, Zika, and dengue viruses are transmitted by Aedes aegypti mosquitoes. Since these viruses co-circulate in several regions, coinfection in humans and vectors may occur, and human coinfections have been frequently reported. Yet, little is known about the molecular aspects of virus interactions within hosts and how they contribute to arbovirus transmission dynamics. We have previously shown that Aedes aegypti exposed to chikungunya and Zika viruses in the same blood meal can become coinfected and transmit both viruses simultaneously. However, mosquitoes may also become coinfected by multiple, sequential feeds on single infected hosts. Therefore, we tested whether sequential infection with chikungunya and Zika viruses impacts mosquito vector competence. We exposed Ae. aegypti mosquitoes first to one virus and 7 days later to the other virus and compared infection, dissemination, and transmission rates between sequentially and single infected groups. We found that coinfection rates were high after sequential exposure and that mosquitoes were able to co-transmit both viruses. Surprisingly, chikungunya virus coinfection enhanced Zika virus transmission 7 days after the second blood meal. Our data demonstrate heterologous arbovirus synergism within mosquitoes, by unknown mechanisms, leading to enhancement of transmission under certain conditions.


2016 ◽  
Vol 29 (12) ◽  
pp. 990-1003 ◽  
Author(s):  
Hua Li ◽  
Zhanquan Zhang ◽  
Chang He ◽  
Guozheng Qin ◽  
Shiping Tian

The NADPH oxidase (NOX) complex has been shown to play a crucial role in stress response and in the virulence of various fungal pathogens. The underlying molecular mechanisms of NOX, however, remain largely unknown. In the present study, a comparative proteomic analysis compared changes in protein abundance in wild-type Botrytis cinerea and ΔbcnoxR mutants in which the regulatory subunit of NOX was deleted. The ΔbcnoxR mutants exhibited reduced growth, sporulation, and impaired virulence. A total of 60 proteins, representing 49 individual genes, were identified in ΔbcnoxR mutants that exhibited significant differences in abundance relative to wild-type. Reverse transcription-quantitative polymerase chain reaction analysis demonstrated that the differences in transcript levels for 36 of the genes encoding the identified proteins were in agreement with the proteomic analysis, while the remainder exhibited reverse levels. Functional analysis of four proteins that decreased abundance in the ΔbcnoxR mutants indicated that 6-phosphogluconate dehydrogenase (BcPGD) played a role in the growth and sporulation of B. cinerea. The Δbcpgd mutants also displayed impaired virulence on various hosts, such as apple, strawberry, and tomato fruit. These results suggest that NOX can influence the expression of BcPGD, which has an impact on growth, sporulation, and virulence of B. cinerea.


Homeopathy ◽  
2018 ◽  
Vol 108 (01) ◽  
pp. 043-053 ◽  
Author(s):  
José Mazón-Suástegui ◽  
Joan Salas-Leiva ◽  
Andressa Teles ◽  
Dariel Tovar-Ramírez

Background This research aimed to observe the effect of homeopathic treatments prepared from Vibrio parahaemolyticus and V. alginolyticus (H1) and commercial homeopathic medication Phosphoricum acidum and Silicea terra (H2) on the immune and antioxidant response in Seriola rivoliana juveniles under usual culture conditions and challenged with V. parahaemolyticus. Materials and Methods Quantitative polymerase chain reaction analysis was used to study changes in the expression of key genes related to immune response, cytokines (interleukin-1β [IL-1β]), adapter protein for cytokine release (MyD88) and piscidin and spectrophotometric techniques to analyze the activity of antioxidant superoxide dismutase (SOD) and catalase (CAT) enzymes in Seriola rivoliana juveniles at 30 (weaning stage [WS]) and 60 (early juveniles [EJ]) days post-hatching. Results The H1 treatment led to over-expression of the IL-1β and MyD88 genes in fish at WS and EJ with respect to control, contrary to the H2 treatment that led to under-expression of the IL-1β, MyD88 and piscidin genes at the EJ stage. In fish challenged with V. parahaemolyticus, both H1 and H2 led to over-expression of IL-1β and MyD88; H2 caused an over-expression of piscidin. The SOD activity was higher in H1 with respect to H2 and the control group. CAT remained relatively stable with both H1 and H2 treatments. Conclusions The results suggest that the overall effect of H1 was due to the presence of unknown antigens in low concentrations, while the response to H2—specifically during challenge—may have been due to a stimulating effect of nano-structures, prevailing from mother tincture after sequential dilution/succussion, in a pathway similar to that attributed to nano-vaccines.


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