Dataset Information

Chromosome-level genome assemblies of the malaria vectors Anopheles coluzzii and Anopheles arabiensis.

ABSTRACT:

Background

Anopheles coluzzii and Anopheles arabiensis belong to the Anopheles gambiae complex and are among the major malaria vectors in sub-Saharan Africa. However, chromosome-level reference genome assemblies are still lacking for these medically important mosquito species.

Findings

In this study, we produced de novo chromosome-level genome assemblies for A. coluzzii and A. arabiensis using the long-read Oxford Nanopore sequencing technology and the Hi-C scaffolding approach. We obtained 273.4 and 256.8 Mb of the total assemblies for A. coluzzii and A. arabiensis, respectively. Each assembly consists of 3 chromosome-scale scaffolds (X, 2, 3), complete mitochondrion, and unordered contigs identified as autosomal pericentromeric DNA, X pericentromeric DNA, and Y sequences. Comparison of these assemblies with the existing assemblies for these species demonstrated that we obtained improved reference-quality genomes. The new assemblies allowed us to identify genomic coordinates for the breakpoint regions of fixed and polymorphic chromosomal inversions in A. coluzzii and A. arabiensis.

Conclusion

The new chromosome-level assemblies will facilitate functional and population genomic studies in A. coluzzii and A. arabiensis. The presented assembly pipeline will accelerate progress toward creating high-quality genome references for other disease vectors.

SUBMITTER: Zamyatin A

PROVIDER: S-EPMC7957348 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Publications

Chromosome-level genome assemblies of the malaria vectors Anopheles coluzzii and Anopheles arabiensis.

Zamyatin Anton A Avdeyev Pavel P Liang Jiangtao J Sharma Atashi A Chen Chujia C Lukyanchikova Varvara V Alexeev Nikita N Tu Zhijian Z Alekseyev Max A MA Sharakhov Igor V IV

GigaScience 20210301 3

<h4>Background</h4>Anopheles coluzzii and Anopheles arabiensis belong to the Anopheles gambiae complex and are among the major malaria vectors in sub-Saharan Africa. However, chromosome-level reference genome assemblies are still lacking for these medically important mosquito species.<h4>Findings</h4>In this study, we produced de novo chromosome-level genome assemblies for A. coluzzii and A. arabiensis using the long-read Oxford Nanopore sequencing technology and the Hi-C scaffolding approach. W ...[more]

PMID: 33718948

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Project description:BackgroundUnderstanding the biology of malaria vector mosquitoes is crucial to understanding many aspects of the disease, including control and future outcomes. The development rates and survival of two Afrotropical malaria vectors, Anopheles arabiensis and Anopheles funestus, are investigated here under conditions of constant and fluctuating temperatures. These data can provide a good starting point for modelling population level consequences of temperature change associated with climate change. For comparative purposes, these data were considered explicitly in the context of those available for the third African malaria vector, Anopheles gambiae.MethodsTwenty five replicates of 20-30 eggs were placed at nine constant and two fluctuating temperatures for development rate experiments and survival estimates. Various developmental parameters were estimated from the data, using standard approaches.ResultsLower development threshold (LDT) for both species was estimated at 13-14°C. Anopheles arabiensis developed consistently faster than An. funestus. Optimum temperature (Topt) and development rate at this temperature (μmax) differed significantly between species for overall development and larval development. However, Topt and μmax for pupal development did not differ significantly between species. Development rate and survival of An. funestus was negatively influenced by fluctuating temperatures. By contrast, development rate of An. arabiensis at fluctuating temperatures either did not differ from constant temperatures or was significantly faster. Survival of this species declined by c. 10% at the 15°C to 35°C fluctuating temperature regime, but was not significantly different between the constant 25°C and the fluctuating 20°C to 30°C treatment. By comparison, previous data for An. gambiae indicated fastest development at a constant temperature of 28°C and highest survival at 24°C.ConclusionsThe three most important African malaria vectors all differ significantly in development rates and survival under different temperature treatments, in keeping with known distribution data, though differences among M and S molecular forms of An. gambiae likely complicate the picture. Increasing temperatures associated with climate change favour all three species, but fluctuations in temperatures are detrimental to An. funestus and may also be for An. gambiae. This may have significant implications for disease burden in areas where each species is the main malaria vector.

Dataset Information

Chromosome-level genome assemblies of the malaria vectors Anopheles coluzzii and Anopheles arabiensis.

Background

Findings

Conclusion

Publications

Chromosome-level genome assemblies of the malaria vectors Anopheles coluzzii and Anopheles arabiensis.

Similar Datasets

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