Affinities and divergence of Aedes mosquitoes using bayesian relaxed clock and complex models of evolution

Affinities and Divergence of Aedes mosquitoes

using bayesian relaxed clock and complex

models of evolution

Nicola Zadra

_{, Annapaola Rizzoli}

_{and Omar Rota Stabelli}

1_{Cibio – Centre for Integrative Biology, University of Trento, (TN) Italy;} 2_{Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige (TN), Italy}

INCONGRUENCE BETWEEN NUCLEAR AND MITOCHONDRIAL

DATA

We performed Bayesian phylogenetic and clock analysis using separately nuclear and mitochondrial genes (Fig. 1). We detected

various topological incongruence which may reflect ancient

introgressions. The mitochondrial tree is unresolved at many nodes, therefore incongruences are poorly supported: whole mitochondrial

genome is needed to confirm ancient hybridisations/introgression

events.

Although the age of Culicidae, Culicinae, and Aedini is similar among the two trees, the split between A. aegypti and A. albopictus ranges from circa 80 my using mitochondrial data to circa 30 my using nuclear data. Some of these incongruence can be explained by a biased sampling of genes in the datasets, but also by peculiar inheritance and genetic differences between nuclear and mitochondrial DNA.

AEDINI: MOSQUITOES OF BIOLOGICAL

AND MEDICAL IMPORTANCE

Mosquitoes are the indirect cause of more morbidity and mortality among humans that any other group of organisms. Mosquito (Culicidae) are divided in two main clades Culicinae and Anohelinae.

Culicinae includes 3,559 species classified in two subfamilies and 113 genera. One third of these species belong to the tribe Aedini: they are notorious (and unfortunately excellent) vectors of a variety of viruses (arboviruses), filarial worms (helminths) and protozoans.

Brief methods

We analysed two different concatenate dataset Nuclear (28S, 18S, Enolase, Arginine-Kinase) and mitochondrial (16S, CoxI, CoxII, NAD4). The analysis were carried out using Beast2, RaxML and PhyloBayes using GTR+G and CAT+G replacement models. Model test revealed the Yule+ relaxed lognormal clock as the best fitting tree and clock model for our dataset in BEAST2. For calibration, we used two minimum fossil calibration point within Anopheles and Culex, plus a root prior for the split between Mosquito and Drosophilinae (as in Benton et al., 2006).

PERSEPCTIVES: A FRAMWEORK FOR EVOLUTIONARY

AND MANAGEMNT STUDIES

Our estimates indicate that emerging models such as A. albopictus can be currently compared only against distantly related species (A. aegyptyi, circa 75 million years divergence). Our data indicate that comparative genomic of A. albopictus would provide much more detailed results if compared with closer related sister species

A. flavopictus (20-5 million years ago depending on the marker).

We advocate that sequencing the genome of the latter would allow a better interpretation of genomic features such as odorant receptors in A. albopictus (fig. 3).

Contact info:nicola.zadra@guest.fmach.it

POOR KNOWLEDGE OF AEDINAE

DIVERGENCE TIME IMPAIR BIOLOGICAL

STUDIES.

Knowledge of Aedini genetic diversity is still scattered and incomplete (only two genomes sequenced so far, (Gasperi at al., 2015; Nane et

al., 2007 ). In particular, the divergence time of

Aedini has yet to be inferred using molecules. In order to improve our understanding of their

evolution, we present the first multigene

estimate of Aedini divergences based on Bayesian inference and fossil calibrations. Results are helpful to provide a paleo-biological background to understand present Aedini ecology and to ease genomic studies aimed at ameliorating their control

THE EVOLUTIONARY HISTORY OF AEDEINAE AND OTHER MOSQUITOES

Our concatenated analysis of mitochondrial + nuclear data (spanning 8 genes and 7494 nucleotides) allows us to obtain a first picture of Aedini evolutionary history. Our tree indicate two monophyletic groups of Aedini, one of which likely indicating the proposed new genus Ochlerotatus. Mosquitos (Culicidae) diverged approximately 180 million years ago, quite concomitant with the divergence of flowering plants (James A. Doyle 2012; Misof B. et al., 2014) consistent with the Culicidae habit of feeding on nectar. Aedini originated from other Culicinae circa 114 million years ago, concomitant with angiosperm diversification, and the first bird and mammals diversifications: this suggests interesting co-evolutionary scenarios. A.aegypti A. flavopictus A. albopictus A. albopictus other Aedes 40 new OR in A. albopictus (Chen e tal. 2015) ? 75? 25? 0 mya

Reference

Benton, Michael J., and Philip CJ Donoghue. "Paleontological evidence to date the tree of life." Molecular biology and evolution24.1 (2006): 26-53.

Chen, Xiao-Guang, et al. "Genome sequence of the Asian Tiger mosquito, Aedes albopictus, reveals insights into its biology, genetics, and evolution." Proceedings of the National Academy of Sciences 112.44 (2015): E5907-E5915.

Doyle, James A. "Molecular and fossil evidence on the origin of angiosperms." Annual review of earth and planetary sciences 40 (2012): 301-326.

Dritsou, Vicky, et al. "A draft genome sequence of an invasive mosquito: an Italian Aedes albopictus." Pathogens and global health 109.5 (2015): 207-220

Misof, Bernhard, et al. "Phylogenomics resolves the timing and pattern of insect evolution." Science 346.6210 (2014): 763-767.

Nene, Vishvanath, et al. "Genome sequence of Aedes aegypti, a major arbovirus vector." Science (2007). 0 50 100 150 200 250 Aedes luteocephalus Ochlerotatus triseriatus Aedes taylori Ochlerotatus vigilax Psorophora howardii Anopheles gambiae Aedes palauensis Ochlerotatus dorsalis Mimomyia Malaya Sabethes Ochlerotatus taeniorhynchus Chagasia Wyeomyia smithii Aedes albopictus Aedes koreicus Haemagogus janthinomys Culiseta Culex tritaeniorhynchus Aedes dybasi Armigeres subalbatus Aedes togoi Culex quinquefasciatus Lutzia Ochlerotatus japonicus Bironella Aedes subalbopictus Aedes albolineatus Aedes flavopictus Psorophora ferox Coquillettidia crassipes Uranotaenia lowii Tanakaius savoryi Catageiomyia argenteopunctata Aedes furcifer Toxorhynchites Aedes vexans Aedes aegypti Aedes notoscriptus Ochlerotatus caspius 1 0,97 1 0,91 0,98 0,97 1 1 1 1 0,97 1 0,99 0,91 1 0,6 1 1 1 1 1 1 0 50 100 150 200, 250, Aedes luteocephalus Ochlerotatus dorsalis Psorophora ferox Ochlerotatus triseriatus Ochlerotatus taeniorhynchus Lutzia Aedes subalbopictus Aedes togoi Coquillettidia crassipes Wyeomyia smithii Bironella Tanakaius savoryi Uranotaenia lowii Chagasia Aedes albopictus Aedes albolineatus Aedes koreicus Malaya Sabethes Aedes palauensis Armigeres subalbatus Aedes notoscriptus Toxorhynchites Mimomyia Aedes vexans Culex tritaeniorhynchus Aedes dybasi Psorophora howardii Aedes flavopictus Haemagogus janthinomys Culiseta Anopheles gambiae Ochlerotatus caspius Aedes taylori Ochlerotatus vigilax Culex quinquefasciatus Aedes furcifer Aedes aegypti Catageiomyia argenteopunctata Ochlerotatus japonicus 1 0,98 1 0,99 0,98 1 0,99 0,92 0,99 1 1 1 1 0,99 1 1 0,97 1 0,99 0,97 0,97 1 0,94 1 1 1 0,99 1 1

Fig1. Mitocondrial (tree above) and Nuclar (tree below) time trees. Lines connect the same node in the two datted phylogenies, only posterior probability higher than 0.9 are shown.

Aedini Group 1 Aedini Group 2 Aedini Aedini Group 1 Aedini Group 2 Aedini Culicini Anophelinae Culicini Anophelinae Culicinae

Fig2. Divergence estimates using beast2 and the concatenated dataset. The gray curves are the distribution of the 95% posterior probability limit for the age of the Culicidae and Aedini origin. Dotted lines indicate the split between A. albopictus and A. aegypty and A. flavopicus.

Aedes (Stegomyia) luteocephalus

Aedes( Ochlerotatus) taeniorhynchus

Psorophora ferox Aedes (Ochlerotatus) triseriatus

Aedes (Ochlerotatus) dorsalis

Anopheles gambiae Aedes (Stegomyia) palauensis

Aedes (Tanakaius) togoi

Malaya

Coquillettidia Culex quinquefasciatus Aedes (Tanakaius) savoryi

Chagasia Lutzia Aedes (Stegomyia) albopictus

Aedes (Scutomyia) albolineatus

Aedes (Hulecoeteomyia) koreicus

Sabethes

Uranotaenia Aedes (Stegomyia) dybasi

Armigeres subalbatus

Aedes (Rampamyia) notoscriptus

Wyeomyia Mimomyia Aedes (Diceromyia) furcifer

Bironella Aedes (Stegomyia) subalbopictus

Psorophora howardii Aedes (Stegomyia) flavopictus

Aedes (Ochlerotatus) caspius

Toxorhynchites.

Culiseta Haemagogus janthinomys Aedes (Catageiomyia) argenteopunctata

Aedes (Ochlerotatus) vigilax

Culextritaeniorhynchus Aedes (Aedimorphus) vexans Aedes (Stegomyia) aegypti

Aedes (Diceromyia) taylori

Aedes (Ochlerotatus) japonicus 0,95 1 0,94 0,98 1 1 0,99 1 1 0,97 0,98 1 1 1 1 1 1 1 1 0,97 1 1 0,98 1 0,93 1 1 1 1 1 200 150 100 50 0 250 300 Neo Permian Paleozoic Mesozoic

Triassic Jurassic Cretaceous

Cenozoic Paleogene Neo. Aedini radiation

Mosquito radiation

A. aeg-A. alb split

A. alb-A.fla split Aedini Group 1 Aedini Group 2 Culicini Anophelinae Angiosperm Other Culicinae (Ochelorotatus?) (Aedes sensu stricto) Culicinae Culicidae Aedinii

Fig3. Here we stress how the sister species genetic and genomics studies will help the understanding of the biological and ecological key innovation in A. albopictus, using a coparative genomics approch.