Compact genome of the Antarctic midge is likely an adaptation to an extreme environment

• Published in: Nature Communications
• Main Authors: Kelley, Joanna, Peyton, Justin, Fiston-Lavier, Anna-Sophie, Teets, Nicholas, Yee, Muh-Ching, Johnston, J. Spencer, Bustamante, Carlos, Lee, Richard, Denlinger, David
• Other Authors: Department of Genetics Stanford, Stanford Medicine, Stanford University-Stanford University, School of Biological Sciences, Washington State University (WSU), Ohio State University Columbus (OSU), Stanford University, Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement IRD : UR226-Centre National de la Recherche Scientifique (CNRS), University of Florida Gainesville (UF), Department of Plant Biology Carnegie (DPB), Carnegie Institution for Science, Texas A&M University College Station, Miami University Ohio (MU)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2014
• Subjects: [SDV.GEN.GA]Life Sciences [q-bio]/Genetics/Animal genetics; [SDV.BA.ZI]Life Sciences [q-bio]/Animal biology/Invertebrate Zoology; Antarc*; Antarctic; Antarctic midge; Antarctica; Belgica antarctica
• Online Access: https://hal.umontpellier.fr/hal-03025771; https://hal.umontpellier.fr/hal-03025771/document; https://hal.umontpellier.fr/hal-03025771/file/ncomms5611.pdf; https://doi.org/10.1038/ncomms5611

International audience The midge, Belgica antarctica, is the only insect endemic to Antarctica, and thus it offers a powerful model for probing responses to extreme temperatures, freeze tolerance, dehydration, osmotic stress, ultraviolet radiation and other forms of environmental stress. Here we present the first genome assembly of an extremophile, the first dipteran in the family Chironomidae, and the first Antarctic eukaryote to be sequenced. At 99 megabases, B. antarctica has the smallest insect genome sequenced thus far. Although it has a similar number of genes as other Diptera, the midge genome has very low repeat density and a reduction in intron length. Environmental extremes appear to constrain genome architecture, not gene content. The few transposable elements present are mainly ancient, inactive retroelements. An abundance of genes associated with development, regulation of metabolism and responses to external stimuli may reflect adaptations for surviving in this harsh environment.