Methods and Protocols M ETHODS in MOLECULAR BIOLOGY™

Methods in Molecular Biology 1068 Kazushige Touhara Editor Pheromone Signaling Methods and Protocols M ETHODS IN MOLECULAR BIOLOGY™ Series Editor John M. Walker School of Life Sciences University of Hertfordshire Hat fi eld, Hertfordshire, AL10 9AB, UK For further volumes: http://www.springer.com/series/7651 Pheromone Signaling Methods and Protocols Edited by Kazushige Touhara Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan Editor Kazushige Touhara Department of Applied Biological Chemistry Graduate School of Agricultural and Life Sciences The University of Tokyo Tokyo , Japan ISSN 1064-3745 ISSN 1940-6029 (electronic) ISBN 978-1-62703-618-4 ISBN 978-1-62703-619-1 (eBook) DOI 10.1007/978-1-62703-619-1 Springer New York Heidelberg Dordrecht London Library of Congress Control Number: 2013947162 © Springer Science+Business Media, LLC 2013 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifi cally for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Printed on acid-free paper Humana Press is a brand of Springer Springer is part of Springer Science+Business Media (www.springer.com) Pref ace Many animal species utilize chemosensory systems to detect a variety of chemical substances in the external environment. When these substances convey information regard- ing food, predators, species, or sex, it is considered chemical communication between organisms. The notion of chemical communication was fi rst proposed by Charles Darwin in the late nineteenth century, in conjunction with the physical signal-mediated communication described for the visual and auditory systems. At approximately the same time, Jean Henri Fabre described the attraction of male moths by conspecifi c females, and proposed that the cue was not a visual signal but some kind of smell. The concept of chemical interaction was scientifi cally recognized when Albrecht Beth proposed in 1932 the term “ectohormone” for substances that functioned like a hormone but were secreted into the external environment. The fi rst molecular evidence for a substance that was able to mediate chemical communication was obtained when Butenandt discovered bombykol, the sex pheromone of the silk moth Bombyx mori , in 1959, which is released by females and elicits the full sequence of sexual behavior in male moths [1]. The term “pheromone” was then defi ned by Karlson and Luscher as “substances which are secreted to the outside by an individual and received by a second individual of the same species, in which they release a specifi c reaction, for example, a defi nite behavior or developmental process” [2]. Pheromone is a combined term from the Greek words pherein for “to bear or transfer” and hormao for “to excite.” Specifi c reactions by pheromones are generally categorized into two types: one that releases a visible stereotyped behavior such as attraction or avoidance and a second that elicits endo- crinological changes such as puberty acceleration and estrous cycle regulation. A pheromone appears to be a type of smell recognized by some species; however, the defi nition specifi cally avoids any use of the terms “odor” or “odorant.” It does not even defi ne pheromones as being volatile. Karlson and Luscher were shown to be insightful in this regard, as future research was to fi nd that pheromones can be nonvolatile substances including relatively large organic compounds, peptides, and proteins. Recently, there has been some contention in the fi eld as to whether the defi nition of pheromones should be extended, as pheromones appear to play far more diverse functional roles than previously defi ned. Possible criteria for a more inclusive defi nition of a pheromone may be that (1) pheromones are released by one individual and received by conspecifi cs; (2) pheromones themselves may convey meaningful information including sex, strain, and species to the receiver; and (3) pheromonal effects are stereotyped or innate. It is of note that the same molecule may be utilized as a pheromone in different species. It is also important to note that pheromones are distinct from individual chemical information that may be learned [3]. The mechanisms underlying pheromone action are also of signifi cance. A receptor that senses insect sex pheromone was fi rst discovered in the silk moth. The bombykol receptor was identifi ed as a male-specifi c seven transmembrane protein that appeared to belong to the olfactory receptor superfamily, and that which showed a highly specifi c and sensitive v vi Preface response to bombykol [4]. It was later found that the mechanism of signal transduction was distinct from the one observed in vertebrates where the insect pheromone receptors formed a heteromeric ligand-gated cation channel complex [5, 6]. The electrical signal is transmitted to specifi c glomeruli in the antennal lobe, the fi rst center of the olfactory sensory path- way, and integrated in the higher brain to elicit sexual behavior. In vertebrates, volatile pheromones are detected by the main olfactory system in addi- tion to the secondary olfactory system called the vomeronasal organ located at the bottom of the nasal cavity [7]. The vomeronasal system was identifi ed in amphibians, rodents, and some primate species and detects not only volatile cues but also nonvolatile pheromones. The old-world monkeys and humans do not possess a vomeronasal organ, but rather detect pheromones in the main olfactory system, if at all. The receptors belong to the G protein- coupled receptor superfamily including the olfactory receptor (OR), trace amine-associated receptor (TAAR), and vomeronasal receptor (VR). The signal is further transmitted to the main or accessory olfactory bulb and subsequently conveyed to the higher brain areas responsible for specifi c behavioral and neuroendocrinological output. The development of molecular biology and neuroscience techniques has permitted the precise method of pheromone action from the molecule to the receptor to be defi ned [7]. The next aim of pheromone research is to further our understanding of how pheromone information is integrated in the brain, and how specifi c behavioral output is regulated by the neural circuitry. The pheromone system is an ideal model for understanding the neural networks that lead to various adaptive behaviors. Another important area to investigate is whether humans also impart chemical communication via pheromones. Given humans have evolved visual and auditory senses as their major cue, it seems appropriate to suggest that meaningful chemical communication does not exist in humans today. However, it is also true that humans often feel appeased by the smell of infants. Menstrual synchrony in females living closely together is also another example of potential chemical communication within the human species [8]. In contrast, rodents appear to heavily rely on chemical communication throughout life. A full list of required compounds and their receptors, however, is yet to be fully revealed. The mechanism underlying how a selective pressure occurred on sensory systems so that each animal developed a sophisticated and individually tailored chemical communication strategy remains unknown. The strategy is thought to be optimal for the survival of each organism under their living environment. In this regard, the evolution- ary history of changes in pheromone molecules and genome related to pheromone recep- tion will tell us where we came from and in which direction we are headed. Over the last decade, a great deal of progress has been made into understanding the molecular mechanisms underlying pheromone action, largely due to the discovery of receptor genes and the advancement of imaging techniques. The major goal of Pheromone Signaling is to provide experimental methods and protocols that allow us to perform pheromone research in a variety of organisms ranging from invertebrates to vertebrates.

Load more