Figure 2

Evolutionary relationships of UCP1-3 family members. We have reconstructed a phylogeny using a total of 161 protein sequences of UCP1-4 retrieved from GenBank, and aligned using Mafft v. 6.626 with the L-INS-i strategy. A final alignment of 281 positions was obtained after removing ambiguous positions using Gblocks v.0.91b. The JTT+I+G was selected as the best-fit evolutionary model using Prottest v. 2.0. The maximum likelihood tree (-lnL = 15417.6) was inferred using PhyML v. 2.4.4 with midpoint rooting. An approximately unbiased test performed using RaxMLv. 7.0.4 and Consel v. 0.1 determined that the constrained tree (-lnL = 15433.2) shown in the figure was not significantly different (P > 0.05) and, thus, within the confidence set. Bootstrap analysis was performed using RaxML at the Cipres Portal, and bootstrap values for relevant nodes are shown in the tree. Taxonomic groups are represented by different colors. Inset: phylogeny of mitochondrial carrier proteins adapted from [6]. Our reconstructed phylogeny shows animal UCP4 and UCP5 (also termed BMCP1) as a sister group of plant UCPs and animal UCP1-3. The other members of the superfamily analyzed – PiC, ANT, OGC (oxoglutarate carrier) and DIC (dicarboxylate carrier) – were found to be more distantly related paralogs.