title: Transcriptional Differences between Diapausing and Non-Diapausing D. montana Females Reared under the Same Photoperiod and Temperature.
abstract: BACKGROUND
  A wide range of insects living at higher latitudes enter diapause at the end of the warm season, which increases their chances of survival through harsh winter conditions. In this study we used RNA sequencing to identify genes involved in adult reproductive diapause in a northern fly species, Drosophila montana. Both diapausing and non-diapausing flies were reared under a critical day length and temperature, where about half of the emerging females enter diapause enabling us to eliminate the effects of varying environmental conditions on gene expression patterns of the two types of female flies.
  
  
  RESULTS
  RNA sequencing revealed large differences between gene expression patterns of diapausing and non-diapausing females, especially in genes involved with metabolism, fatty acid biosynthesis, and metal and nucleotide binding. Differently expressed genes included several gene groups, including myosin, actin and cytochromeP450 genes, which have been previously associated with diapause. This study also identified new candidate genes, including some involved in cuticular hydrocarbon synthesis or regulation (desat1 and desat2), and acyl-CoA Δ11-desaturase activity (CG9747), and few odorant-binding protein genes (e.g. Obp44A). Also, several transposable elements (TEs) showed differential expression between the two female groups motivating future research on their roles in diapause.
  
  
  CONCLUSIONS
  Our results demonstrate that the adult reproductive diapause in D. montana involves changes in the expression level of a variety of genes involved in key processes (e.g. metabolism and fatty acid biosynthesis) which help diapausing females to cope with overwintering. This is consistent with the view that diapause is a complex adaptive phenotype where not only sexual maturation is arrested, but also changes in adult physiology are required in order to survive over the winter.
authors: Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, Jyväskylä, Finland.
authors: Maaria
authors: M
authors: Kankare
authors: Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, Jyväskylä, Finland.|Centre for Biological Diversity, School of Biology, University of St Andrews, Fife, KY16 9TH, St Andrews, United Kingdom.
authors: Darren J
authors: DJ
authors: Parker
authors: Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, Jyväskylä, Finland.
authors: Mikko
authors: M
authors: Merisalo
authors: BioMediTech, Biokatu 6, F1-33014, University of Tampere, Tampere, Finland.
authors: Tiina S
authors: TS
authors: Salminen
authors: Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, Jyväskylä, Finland.
authors: Anneli
authors: A
authors: Hoikkala
mesh_terms: D000199:Actins / Q000235:genetics / Q000378:metabolism; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D064666:Diapause, Insect / Q000502:physiology*; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D008675:Metamorphosis, Biological; D009218:Myosins / Q000235:genetics / Q000378:metabolism; D017440:Photoperiod; D012098:Reproduction / Q000235:genetics / Q000502:physiology; D013696:Temperature
chemical_list: D000199:Actins; D029721:Drosophila Proteins; D003577:Cytochrome P-450 Enzyme System; D009218:Myosins