Yellow-y Functions in Egg Melanization and Chorion Morphology of the Asian Tiger Mosquito, Aedes albopictus

The Asian tiger mosquito, Aedes albopictus, is one of the most serious public health pests, which can transmit various vector-borne diseases. Eggs from this mosquito species become dark black shortly after oviposition and exhibit high desiccation resistance. Some of the Yellow proteins that act as dopachrome conversion enzymes (DCEs) are involved in the tyrosine-mediated tanning (pigmentation and sclerotization) metabolic pathway that significantly accelerates melanization reactions in insects. In this research, we analyzed the function of one of the yellow genes, yellow-y (AalY-y), in eggshell/chorion melanization of Ae. albopictus eggs. Developmental and tissue-specific expression measured by real-time PCR showed that AalY-y transcripts were detected at all stages of development analyzed, with significantly higher levels in the ovaries from blood-fed adult females. Injection of double-stranded RNA for AalY-y (dsAalY-y) had no significant effect on fecundity. However, unlike dsEGFP-treated control eggs that become black by 2–3 h after oviposition (HAO), dsAalY-y eggs were yellow-brown at 2 HAO, and reddish-brown even at 48 HAO. dsEGFP eggs exhibited resistance to desiccation at 48 HAO, whereas approximately 50% of the dsAalY-y eggs collapsed when they were moved to a low humidity condition. In addition, TEM analysis revealed an abnormal morphology and ultrastructure of the outer-endochorion in the dsAalY-y eggs. These results support the hypothesis that AalY-y is involved in the tyrosine-induced melanin biosynthetic pathway, plays an important role in black melanization of the chorion and functions in conferring proper morphology of the outer-endochorion, a structure that is presumably required for egg desiccation resistance in Ae. albopictus.

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Wolbachia strain wAu efficiently blocks arbovirus transmission in Aedes albopictus

10.1101/844670 ◽

2019 ◽

Author(s):

Maria Vittoria Mancini ◽

Christie S. Herd ◽

Thomas H. Ant ◽

Shivan M. Murdochy ◽

Steven P. Sinkins

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Mosquito Species ◽

Field Trials ◽

Asian Tiger Mosquito ◽

Native Strain ◽

Promising Tool ◽

Novel Approach ◽

Asian Tiger ◽

Tiger Mosquito

AbstractThe global incidence of arboviral diseases transmitted by Aedes mosquitoes, including dengue, chikungunya, yellow fever, and Zika, has increased dramatically in recent decades. The release of Aedes aegypti carrying the maternally inherited symbiont Wolbachia as an intervention to control arboviruses is being trialled in several countries. However, these efforts are compromised in many endemic regions due to the co-localization of the secondary vector Aedes albopictus, the Asian tiger mosquito. Ae. albopictus has an expanding global distribution following incursions into a number of new territories. To date, only the wMel and wPip strains of Wolbachia have been reported to be transferred into and characterized in this vector. A Wolbachia strain naturally infecting Drosophila simulans, wAu, was selected for transfer into a Malaysian Ae. albopictus line to create a novel triple-strain infection. The newly generated line showed self-compatibility, moderate fitness cost and complete resistance to Zika and dengue infections.Author summaryAedes albopictus, the invasive Asian tiger mosquito, is responsible for numerous outbreaks of important viruses such as dengue and Zika in various regions of the world. The need for alterative control interventions propelled the development of a novel approach that exploits a natural insect symbiont, Wolbachia; when transferred into non-native hosts, these maternally-inherited bacteria are able to interfere with the transmission of mosquito-borne viruses, and also provide reproductive advantages to the host, offering a promising tool for self-sustaining field applications. Currently, several field trials are ongoing for the primary vector of dengue and several other arboviruses, Aedes aegypti, providing encouraging results. In this study, Ae. albopictus has been targeted for a similar approach: this mosquito species naturally carries two strains of Wolbachia. The artificial introduction of a third, non-native strain made this line less able to transmit dengue and Zika viruses and had an impact on its fitness.

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Practical management plan for invasive mosquito species in Europe: I. Asian tiger mosquito (Aedes albopictus)

Travel Medicine and Infectious Disease ◽

10.1016/j.tmaid.2020.101691 ◽

2020 ◽

Vol 35 ◽

pp. 101691 ◽

Cited By ~ 5

Author(s):

Romeo Bellini ◽

Antonios Michaelakis ◽

Dušan Petrić ◽

Francis Schaffner ◽

Bulent Alten ◽

...

Keyword(s):

Aedes Albopictus ◽

Mosquito Species ◽

Management Plan ◽

Asian Tiger Mosquito ◽

Invasive Mosquito Species ◽

Practical Management ◽

Asian Tiger ◽

Invasive Mosquito ◽

Tiger Mosquito

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Yellow-g and Yellow-g2 proteins are required for egg desiccation resistance and temporal pigmentation in the Asian tiger mosquito, Aedes albopictus

Insect Biochemistry and Molecular Biology ◽

10.1016/j.ibmb.2020.103386 ◽

2020 ◽

Vol 122 ◽

pp. 103386 ◽

Cited By ~ 3

Author(s):

Mi Young Noh ◽

Sung Hyun Kim ◽

Maureen J. Gorman ◽

Karl J. Kramer ◽

Subbaratnam Muthukrishnan ◽

...

Keyword(s):

Aedes Albopictus ◽

Desiccation Resistance ◽

Asian Tiger Mosquito ◽

Asian Tiger ◽

Tiger Mosquito

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GoogleTrends reflects the abundance of the Asian tiger mosquito (Aedes albopictus): a call for the web-based surveillance of invasive alien vector species

10.32942/osf.io/t3hae ◽

2020 ◽

Author(s):

Jacopo Cerri ◽

Sandro Bertolino

Keyword(s):

Aedes Albopictus ◽

Causal Effect ◽

Monitoring Program ◽

Cost Effective ◽

Asian Tiger Mosquito ◽

Vector Species ◽

Vector Borne Diseases ◽

Asian Tiger ◽

On Line ◽

Tiger Mosquito

The Asian tiger mosquito (Aedes albopictus) is becoming widespread in Europe, where it can transmit some major arboviruses, including Chikungunya and Dengue. While surveillance initiatives are being implemented and harmonized between states, the spread of A.albopictus is outrunning them and cost-effective surveillance tools are needed.In this study, we tested whether on-line searches on Google can be adopted to monitor the abundance of A.albopictus. By using data from a long-term monitoring program in the Emilia-Romagna region (Italy), we tested whether the monthly level of infestation was causally related to the monthly GoogleTrends index for the species.The logarithm of the level of infestation from A.albopictus had a very strong causal effect over the total volume of Google searches about the species. Our statistical model was highly predictive for the GoogleTrends index, suggesting that this cheap on-line metric can be adopted as a proxy for the real level of infestation from A.albopictus.While GoogleTrends has been adopted to identify and monitor epidemics, including vector-borne diseases, no study tested whether it can reflect the numerical abundance of vector species. To the best of our knowledge, our study, among the few validating GoogleTrends with surveillance data, was the first one opening this possibility. Therefore, we believe that the analysis of on-line search volumes might become an important complement to existing surveillance initiatives for invasive vector species worldwide.

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Asian tiger mosquito (Aedes albopictus) - a threat for Switzerland?

Eurosurveillance ◽

10.2807/ese.13.10.08058-en ◽

2008 ◽

Vol 13 (10) ◽

pp. 3-4 ◽

Cited By ~ 22

Author(s):

M N Wymann ◽

E Flacio ◽

S Radczuweit ◽

N Patocchi ◽

P Lüthy

Keyword(s):

Monitoring System ◽

Aedes Albopictus ◽

Mosquito Species ◽

The United States ◽

Asian Tiger Mosquito ◽

Long Distance ◽

Active Monitoring ◽

Larval Stages ◽

Asian Tiger ◽

Tiger Mosquito

The Asian tiger mosquito, Aedes albopictus (Stegomya albopicta) originating from south-east Asia, has spread primarily by the trade of used tyres to the United States, Europe, Latin America and Africa [1]. In Italy, the mosquito species was first detected in Genoa in 1990 and has since spread to several parts of the country, including border areas with Switzerland [2]. In 2000, an active monitoring system was established in southern Switzerland. The first tiger mosquito was detected in the canton of Ticino in 2003 [3]. Monitoring was gradually intensified due to growing mosquito densities in northern Italy. As the long-distance migration of Ae. albopictus depends on passive transport, the monitoring system consisted of strategically positioned oviposition traps along main traffic axes, including parking lots within industrial complexes, border crossings and shopping centres. In 2007, this monitoring system consisted of over 70 checkpoints with a total of 300 traps. Bi-weekly control visits to all traps were conducted between April and November 2007. As soon as eggs were detected, the surrounding vegetation within a perimeter of about 100 metres was sprayed with permethrin against adult mosquitoes. Stagnant water was treated with Bacillus thuringiensis and in some cases with diflubenzuron to control the larval stages.

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