Zoology 117 (2014) 398–414 Contents lists available at ScienceDirect Zoology journa l ho me pa g e: www. els evier.com/locate/zool Venom regeneration in the centipede Scolopendra polymorpha: evidence for asynchronous venom component synthesis Allen M. Cooper ∗ , Wayne J. Kelln, William K. Hayes Department of Earth and Biological Sciences, Griggs Hall #101, Loma Linda University, 24941 Stewart St., Loma Linda, CA 92350, USA a r t i c l e i n f o Article history: Received 5 February 2014 Received in revised form 21 May 2014 Accepted 27 June 2014 Available online 17 October 2014 Keywords: Chilopoda Scolopendromorpha Venom regeneration Protein synthesis a b s t r a c t Venom regeneration comprises a vital process in animals that rely on venom for prey capture and defense. Venom regeneration in scolopendromorph centipedes likely influences their ability to subdue prey and defend themselves, and may influence the quantity and quality of venom extracted by researchers inves- tigating the venom’s biochemistry. We investigated venom volume and total protein regeneration during the 14-day period subsequent to venom extraction in the North American centipede Scolopendra poly- morpha. We further tested the hypothesis that venom protein components, separated by reversed-phase fast protein liquid chromatography (RP-FPLC), undergo asynchronous (non-parallel) synthesis. During the first 48 h, volume and protein mass increased linearly. Protein regeneration lagged behind volume regeneration, with 65–86% of venom volume and 29–47% of protein mass regenerated during the first 2 days. No additional regeneration occurred over the subsequent 12 days, and neither volume nor pro- tein mass reached initial levels 7 months later (93% and 76%, respectively). Centipede body length was negatively associated with rate of venom regeneration. Analysis of chromatograms of individual venom samples revealed that 5 of 10 chromatographic regions and 12 of 28 peaks demonstrated changes in percent of total peak area (i.e., percent of total protein) among milking intervals, indicating that venom proteins are regenerated asynchronously. Moreover, specimens from Arizona and California differed in relative amounts of some venom components. The considerable regeneration of venom occurring within the first 48 h, despite the reduced protein content, suggests that predatory and defensive capacities are minimally constrained by the timing of venom replacement. © 2014 Published by Elsevier GmbH. 1. Introduction Many animals depend on venom to procure food and/or defend themselves. For such animals, a reduced or depleted venom sup- ply could represent a serious cost in terms of lost prey capture opportunities or diminished defense capabilities (Malli et al., 1998; Haight and Tschinkel, 2003; Hayes, 2008; Currier et al., 2012). Thus, a vital component in the lives of virtually all venomous animals is the process of venom regeneration subsequent to venom usage. Because venom is generally a complex mixture of compounds (Abdel-Rahman et al., 2009; Fry et al., 2009; Undheim and King, 2011) and represents a non-trivial metabolic expense (Billen, 1990; McCue, 2006; Nisani et al., 2007, 2012; Pintor et al., 2010, 2011), natural selection should not only fine-tune the amount of venom carried within an animal’s venom gland(s), but also the rate of pro- duction of venom (Mirtschin et al., 2002). If encounter rates with ∗ Corresponding author. Tel.: +1 707 225 5018; fax: +1 909 558 0259. E-mail address: allenmcooper@gmail.com (A.M. Cooper). prey vary with species, habitat, sex and body size of predator, as they do in snakes (Daltry et al., 1997; da Silva and Aird, 2001), then such factors could potentially influence the rate at which venom is produced (Mirtschin et al., 2002). Moreover, the rate of venom regeneration may vary with biochemical complexity (Nisani, 2008; Nisani et al., 2012). Venom regeneration has been studied in several groups of organisms, including snakes (Kochva, 1960; Rotenberg et al., 1971; De Lucca et al., 1974; Brown et al., 1975; Oron et al., 1978; Willemse et al., 1979; Kochva et al., 1982; Klauber, 1997; McCue, 2006; Luna et al., 2009; Pintor et al., 2010, 2011; Currier et al., 2012) and, to a lesser degree, in invertebrates such as spiders (Kaire, 1963; Freyvogel et al., 1968; Perret, 1977; Boeve et al., 1995; Galindo et al., 2009; Uzenbaev and Lyabzina, 2009), scorpions (Alami et al., 2001; Pimenta et al., 2003; Nisani et al., 2007, 2012), and hymenopterans (Beard, 1971; Owen, 1978; Haight and Tschinkel, 2003; Haight, 2012). However, as yet, there has been no study of venom regeneration in centipedes. The class Chilopoda, part of the subphylum Myriapoda, is divided into five living orders (and one extinct order) of centipedes: Scutigeromorpha, Lithobiomorpha, http://dx.doi.org/10.1016/j.zool.2014.06.007 0944-2006/© 2014 Published by Elsevier GmbH.