Novel Cytochrome P450, cyp6a17 , Is Required for Temperature Preference Behavior in Drosophila Jongkyun Kang1, Jaeseob Kim2, Kwang-Wook Choi1* 1 Department of Biological Sciences, Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea, 2 Aprogen Inc., Yuseong-gu, Daejeon, Korea Abstract Perception of temperature is an important brain function for organisms to survive. Evidence suggests that temperature preference behavior (TPB) in Drosophila melanogaster, one of poikilothermal animals, is regulated by cAMP-dependent protein kinase (PKA) signaling in mushroom bodies of the brain. However, downstream targets for the PKA signaling in this behavior have not been identified. From a genome-wide search for the genes regulated by PKA activity in the mushroom bodies, we identified the cyp6a17 Cytochrome P450 gene as a new target for PKA. Our detailed analysis of mutants by genetic, molecular and behavioral assays shows that cyp6a17 is essential for temperature preference behavior. cyp6a17 expression is enriched in the mushroom bodies of the adult brain. Tissue-specific knockdown and rescue experiments demonstrate that cyp6a17 is required in the mushroom bodies for normal temperature preference behavior. This is the first study, to our knowledge, to show PKA-dependent expression of a cytochrome P450 gene in the mushroom bodies and its role as a key factor for temperature preference behavior. Taken together, this study reveals a new PKA-Cytochrome P450 pathway that regulates the temperature preference behavior. Citation: Kang J, Kim J, Choi K-W (2011) Novel Cytochrome P450, cyp6a17, Is Required for Temperature Preference Behavior in Drosophila. PLoS ONE 6(12): e29800. doi:10.1371/journal.pone.0029800 Editor: Patrick Callaerts, VIB & Katholieke Universiteit Leuven, Belgium Received March 24, 2011; Accepted December 5, 2011; Published December 28, 2011 Copyright: 2011 Kang et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This research was supported by grants from the World Class University Program through the National Research Foundation of Korea funded by the Ministry of Education, Science & Technology, contract grant number R31-2008-000-10071-0. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: Jaeseob Kim is employed by a commercial company (Aprogen Inc.). This does not alter the authors’ adherence to all the PLoS ONE policies on sharing data and material. * E-mail: kchoi100@kaist.ac.kr Introduction Behavioral responses to environmental stimuli, including light, humidity, and temperature, are important for survival of all living organisms. Especially for poikilothermal animals, extreme changes in ambient temperature or persistence for a long time at high or low temperature lead to death. These animals adapt to their body temperature changes by using molecular mechanisms to alter metabolism or by behavioral strategies to choose proper temperature conditions. Drosophila has been widely used as a genetic model for studying a variety of behaviors including learning. Recently, it has also been utilized to study the genetic basis of temperature sensation and temperature preference behavior. In Drosophila, larvae and adult flies show strong temperature preference behavior [1–3]. A family of transient receptor potential (TRP) ion channels plays major roles in the sensation of temperature. For example, Painless, one of the TRP channel (TRPA1) superfamily, is required for sensing nociceptive stimuli over 38uC [4]. Another TRP channel, Pyrexia, is involved in protecting flies against noxious temperature over 40uC [5]. In contrast, Drosophila ANKTM1 TRP family channel participates in temperature selection by opening at warm temperature (24–29uC) [6,7]. Despite extensive studies on the role of Drosophila TRP family channels in temperature sensing, it is not well understood how flies perform specific behavior to choose optimal temperature conditions. Interestingly, recent studies have shown that the mushroom bodies in the brain, which plays a critical role in learning and memory, is important for TPB [8]. Furthermore, cAMP-dependent PKA signaling in the mushroom bodies is not only essential for learning and memory but also for TPB. These studies have provided important clues to the mechanism underlying TPB, but the target genes for PKA signaling have been elusive. Hence, we carried out a genome-wide screen for the genes regulated by PKA to obtain insights into the molecular events underlying TPB. From this screen, we found cyp6a17, a cytochrome P450 superfamily gene, as a PKA downstream factor for TPB. The cytochrome P450 (CYP) family is a diverse group of enzymes. Most CYP proteins are involved in the oxidation of a variety of organic substrates including natural products and detoxification of foreign compounds [9–14]. In Drosophila, there exist about 90 CYPs. Some of these CYP genes are involved in ecdysone hormones synthesis [15–20], male aggressive behavior [21,22] and male mating [23]. However, no CYP genes have been implicated in specific brain functions like temperature sensing behavior. Here, we show that cyp6a17 is regulated by PKA and is required for temperature preference behavior. We demonstrate that cyp6a17 expression in the mushroom bodies is necessary and sufficient for TPB. This study identifies cyp6a17 as an important target of PKA signaling for mediating TPB in the mushroom bodies. PLoS ONE | www.plosone.org 1 December 2011 | Volume 6 | Issue 12 | e29800