title: Phylogenetic Origin and Diversification of RNAi Pathway Genes in Insects.
abstract: RNA interference (RNAi) refers to the set of molecular processes found in eukaryotic organisms in which small RNA molecules mediate the silencing or down-regulation of target genes. In insects, RNAi serves a number of functions, including regulation of endogenous genes, anti-viral defense, and defense against transposable elements. Despite being well studied in model organisms, such as Drosophila, the distribution of core RNAi pathway genes and their evolution in insects is not well understood. Here we present the most comprehensive overview of the distribution and diversity of core RNAi pathway genes across 100 insect species, encompassing all currently recognized insect orders. We inferred the phylogenetic origin of insect-specific RNAi pathway genes and also identified several hitherto unrecorded gene expansions using whole-body transcriptome data from the international 1KITE (1000 Insect Transcriptome Evolution) project as well as other resources such as i5K (5000 Insect Genome Project). Specifically, we traced the origin of the double stranded RNA binding protein R2D2 to the last common ancestor of winged insects (Pterygota), the loss of Sid-1/Tag-130 orthologs in Antliophora (fleas, flies and relatives, and scorpionflies in a broad sense), and confirm previous evidence for the splitting of the Argonaute proteins Aubergine and Piwi in Brachyceran flies (Diptera, Brachycera). Our study offers new reference points for future experimental research on RNAi-related pathway genes in insects.
authors.affiliation: Centre for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Dowling
authors.affiliation: Centre for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pauli
authors.affiliation: Centre for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Donath
authors.affiliation: Centre for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany.|Evolutionary Biology & Ecology, Institute for Biology I, University of Freiburg, Freiburg (Brsg.), Germany.|Australian National Insect Collection, CSIRO National Research Collections Australia, Acton, ACT, Australia.
authors.forename: Karen
authors.initials: K
authors.lastname: Meusemann
authors.affiliation: University of Bonn, Institute of Evolutionary Biology and Ecology, Bonn, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Podsiadlowski
authors.affiliation: Centre for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany.
authors.forename: Malte
authors.initials: M
authors.lastname: Petersen
authors.affiliation: Arthropod Department, Zoological Research Museum Alexander Koenig, Bonn, Germany.
authors.forename: Ralph S
authors.initials: RS
authors.lastname: Peters
authors.affiliation: Centre for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Mayer
authors.affiliation: China National GeneBank, BGI-Shenzen, Shenzhen, Guangdong Province, China.|Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Shanlin
authors.initials: S
authors.lastname: Liu
authors.affiliation: Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing, China.|College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Centre for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Misof
authors.affiliation: Centre for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Bonn, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Niehuis
mesh_terms: D000818:Animals; D060565:Argonaute Proteins / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics; D019143:Evolution, Molecular; D049750:Genome, Insect; D019476:Insect Proteins / Q000235:genetics; D007313:Insecta / Q000235:genetics*; D010448:Peptide Initiation Factors / Q000235:genetics; D010802:Phylogeny; D034622:RNA Interference; D016601:RNA-Binding Proteins / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics
chemical_list: D060565:Argonaute Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D010448:Peptide Initiation Factors; C478068:R2D2 protein, Drosophila; D016601:RNA-Binding Proteins; C436124:aub protein, Drosophila; C116498:piwi protein, Drosophila
keywords: RNA interference; argonaute; dicer; evolution; r2d2