Fig. 4

FSD3S contains a putative transmembrane helix domain. The transmembrane helix domain was predicted by bioinformatics analysis (http://www.cbs.dtu.dk/services/TMHMM/). Unlike FSD3 (a), the existence of a transmembrane helix domain was predicted in the C-terminal regions of FSD3S between the 231st and 245th amino acids (b). The black arrow indicates the transmembrane helix domain in the C-terminal regions of FSD3S. A multiple amino acid sequence alignment (c) and histogram (d) show the conservation of the transmembrane helix domains among FSD3S and other membrane or transporter proteins of Arabidopsis, rice, and cyanobacteria. Red boxes in (c) indicate conserved amino acids, with darker red boxes indicating a higher level of conservation