Mitochondrial Pyruvate Carrier 1 and 2 Heterodimer, In Silico, Models of Plant and Human Complexes: A Comparison of Structure and Transporter Binding Properties

Introduction

Plant mitochondrial pyruvate carrier (MPC) had been studied for many years, decades ago (Beechey, Brailsford, & Thompson, 1987; Brailsford, Thompson, Kaderbhai, & Beechey, 1986a, 1986b; Day & Hanson, 1977; Laloi, 1999; Proudlove, Beechey, & Moore, 1987b; Walker & Beevers, 1956), but the plant genes have only recently been discovered (C. Li, Wang, Ma, & Zhang, 2014; M. Wang, Ma, Shen, Li, & Zhang, 2014). There is a role of MPC complex in the abscisic acid (ABA) mediated stomata opening and closing during environmental stress (Santelia & Lawson, 2016; Yu & Assmann, 2014), in addition to energy production, primary metabolism and carbon flux in general. Inner mitochondrial membrane proteins are transported across mitochondrial membranes in plants (Alberts, Johnson, & Lewis, 2002; Duncan, Murcha, & Whelan, 2013; Murcha et al., 2014) similar to that in humans (Kühlbrandt, 2015; Neupert & Herrmann, 2007); indicating that the structural characteristics of the functional proteins might be similar. Overall, this information is useful for in silico biosimulations of metabolism in plants (Beckers et al., 2016; Phelix & Feltus, 2014) and humans (Hammack, Perry, LeBaron, Villareal, & Phelix, 2015; Phelix, Bourdon, Villareal, & LeBaron, 2016; Phelix & Dugan, 2016; Phelix, Villareal, LeBaron, Perry, & Roberson, 2014). For Arabidopsis thaliana and Zea mays this is particularly interesting because full genome-scale metabolic networks are available (Beckers et al., 2016; Saha, Suthers, & Maranas, 2011; Seaver et al., 2015). Understanding membrane transport of pyruvate in plants is critical to engineering plant primary metabolism, in particular for oils and biodiesel production (Lin et al., 2017; Schwender et al., 2015; Weber & Bräutigam, 2013).