The molecular basis of increased desiccation resistance during diapause in the Asian tiger mosquito, Aedes albopictus

Department of Biology, Georgetown University, 37th and O Sts. NW, Washington, DC 20057, USA.
Proceedings of the Royal Society B: Biological Sciences (Impact Factor: 5.05). 09/2010; 277(1694):2683-92. DOI: 10.1098/rspb.2010.0362
Source: PubMed


Photoperiodic diapause is a crucial adaptation to seasonal environmental variation in a wide range of arthropods, but relatively little is known regarding the molecular basis of this important trait. In temperate populations of the mosquito Aedes albopictus, exposure to short-day (SD) lengths causes the female to produce diapause eggs. Tropical populations do not undergo a photoperiodic diapause. We identified a fatty acyl coA elongase transcript that is more abundant under SD versus long-day (LD) photoperiods in mature oocyte tissue of replicate temperate, but not tropical, A. albopictus populations. Fatty acyl CoA elongases are involved in the synthesis of long chain fatty acids (hydrocarbon precursors). Diapause eggs from a temperate population had one-third more surface hydrocarbons and one-half the water loss rates of non-diapause eggs. Eggs from a tropical population reared under SD and LD photoperiods did not differ in surface hydrocarbon abundance or water loss rates. In both a temperate and tropical population, composition of hydrocarbon chain lengths did not differ between eggs from SD versus LD conditions. These results implicate the expression of fatty acyl coA elongase and changes in quantity, but not composition, of egg surface hydrocarbons as important components of increased desiccation resistance during diapause in A. albopictus.

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    • "The worldwide trades in secondhand tires and lucky bamboo, both of which often contain standing water making them ideal places for mosquito eggs and larvae, have been key factors in Ae. albopictus transportation. Once established in a new region, the tiger mosquito easily adapts and persists in a wide range of habitats, even in temperate climates mainly due to its aptitude to enter into a state of dormancy or " diapause " (Urbanski et al., 2010). Undoubtedly, the intrinsic capacities of the mosquito populations largely play an important role in their ecological plasticity. "
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    ABSTRACT: The Asian tiger mosquito Aedes albopictus is one of the most significant pathogen vectors of the twenty-first century. Originating from Asia, it has invaded a wide range of eco-climatic regions worldwide. The insect-associated microbiota is now recognized to play a significant role in host biology. While genetic diversity bottlenecks are known to result from biological invasions, the resulting shifts in host-associated microbiota diversity has not been thoroughly investigated. To address this subject, we compared four autochthonous Ae. albopictus populations in Vietnam, the native area of Ae. albopictus, and three populations recently introduced to Metropolitan France, with the aim of documenting whether these populations display differences in host genotype and bacterial microbiota. Population-level genetic diversity (microsatellite markers and COI haplotype) and bacterial diversity (16S rDNA metabarcoding) were compared between field-caught mosquitoes. Bacterial microbiota from the whole insect bodies were largely dominated by Wolbachia pipientis. Targeted analysis of the gut microbiota revealed a greater bacterial diversity in which a fraction was common between French and Vietnamese populations. The genus Dysgonomonas was the most prevalent and abundant across all studied populations. Overall genetic diversities of both hosts and bacterial microbiota were significantly reduced in recently established populations of France compared to the autochthonous populations of Vietnam. These results open up many important avenues of investigation in order to link the process of geographical invasion to shifts in commensal and symbiotic microbiome communities, as such shifts may have dramatic impacts on the biology and/or vector competence of invading hematophagous insects.
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    • ", 2007 ; Nentwig , 2013 ) . In addition , spiders may reduce their metabolic rate significantly when they experience periods of food limitation ( Ito , 1964 ; Miyashita , 1969 ; Anderson , 1974 ; Tanaka and Ito , 1982 ; Canals et al . , 2007 ; Phillip and Shillington , 2010 ; Stoltz et al . "
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    • "Integration of expert knowledge in modelling approaches demands detailed information on mosquitoes' ecology. In temperate regions, diapausing is a strategy to maintain species' typical life cycle traits, as diapausing eggs show remarkable desiccation resistance aside from increased cold tolerance [53]. In Italy, either favourable microclimates or cold acclimation may play a decisive role in the context of overwin- tering [54]. "
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    No preview · Conference Paper · Aug 2015
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