(a) The protein sequence alignment of human Tspan2 along with CD9 and CD81. The bar graph represents the conservation percentages between each single aa of the concerned tetraspanins. (b) The tree phylogeny of human Tspan2, CD9 and CD81 based on their protein sequence alignment. The phylogram constructed by the RapidNJ plugin, and the Juke-Cantor evolution model used for distance calculation. Scale bar indicates the branch length. All the analysis was performed on CLC Sequence Viewer platform version 7.7.1 (QIAGEN, Aarhus, Denmark).