Figure 7

Phylogenetic tree of plant NRT1/PTRs. Clustering of 52 Arabidopsis, 81 rice and 46 unique barley sequences; for consolidation of the tree, sequences from Alnus glutinosa (AgDCAT1) and Brassica napus (BnNRT1) were included (according to Tsay et al. [14]). Colours indicate membership to subgroups I (green), II (blue), III (orange) and IV (yellow) as defined by Tsay et al. [14]. Barley sequences were derived from RNA-seq, H35 (only full-length sequences), publications (HvPTR1) and previous unpublished work (IPK_HvPTR2, 3, 6). Clustering of NRT1/PTR sequences into different subgroups is supported by the sequence distance matrices (Additional file 5: Figure S4). Detailed version of the phylogenetic tree including ID-numbers of all sequences is given in Additional file 4: Figure S3. For further explanations see legend of Figure 6.