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Nutritional Control of Reproductive Status in Honeybees via DNA Methylation R. Kucharski,* J. Maleszka,* S. Foret, R. Maleszka† Fertile queens and sterile workers are alternative forms of the adult female honeybee that develop from genetically identical larvae following differential feeding with royal jelly. We show that silencing the expression of DNA methyltransferase Dnmt3, a key driver of epigenetic global reprogramming, in newly hatched larvae led to a royal jelly–like effect on the larval developmental trajectory; the majority of Dnmt3 small interfering RNA–treated individuals emerged as queens with fully developed ovaries. Our results suggest that DNA methylation in Apis is used for storing epigenetic information, that the use of that information can be differentially altered by nutritional input, and that the flexibility of epigenetic modifications underpins, profound shifts in developmental fates, with massive implications for reproductive and behavioral status. any organisms respond to environmental conditions by displaying phenotypic plasticity, that is, producing different phenotypes from the same DNA genome (1, 2). In social insects, the production of contrasting adult morphologies as well as different repro-
Molecular Genetics and Evolution, ARC Centre for the Molecular Genetics of Development, Research School of Biological Sciences, Australian National University, Canberra ACT 0200, Australia. *These authors contributed equally to this work. †To whom correspondence should be addressed. E-mail: firstname.lastname@example.org
ductive and behavioral systems is critical to their social organization and division of labor (3–6). These differences are likely to arise at the most basic level from differential somatic imprinting during development on the same genome. Honeybees (Apis mellifera) differentially feed genetically identical female larvae to create mainly workers and, when required, a few queens (7–11). Young nurse bees in the hive produce and feed a largely biochemically uncharacterized substance named royal jelly to larvae destined to become queens, whereas the other larvae are fed with lesssophisticated food (8–11). Despite their identical
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Fig. 1. (A) Injections of Dnmt3 siRNA induce a significant down-regulation of larval Dnmt3 mRNA levels at stage L3....