Fig. 3

a pHMM sequence logo of the 4 microtubule binding domains in the 3 protein subfamilies MAPT, MAP2 and MAP4. More than 1200 individual MTBDs were aligned to build a pHMM and saved as sequence logo in scalar vector graphics format. The interpretation of amino acid distributions and column heights is summarized in Fig. 4 legend. Those sites characterized by Z-scores from SDPPRED as having distinct but conserved aa between the 4 different MTBDs in 3 paralogous subfamilies of a subclassified alignment of the 1200 domains, are shaded and starred as “specificity determining positions” responsible for functional divergence. b The 12 individual subfamily logos enable a direct comparison of all MTBD molecular profiles. The aa replacement of Ile/Val for Cys in the core tubulin binding motif “KCGS” of domains 2 and 3 was the most significant (Z-score 4.64 in A) specificity determining site (starred) and the deletion at position 12 in domains 1–3 differentiates these from domain 4. c SDP sequence logos of 5 sites in MTBD subalignments of 100+ proteins each with the highest Z-scores from SDP-PRED analysis. d Maximum likelihood analysis of the 12 MTBD subalignments of 100+ proteins each (using RAxML, WAG substitution model, 100 bootstrap pseudoalignments and gamma rates with alpha = 1.3). The point of separation of domains 1 and 4 from 2 and 3 was based on a midpoint root reflecting in the evolutionary relatedness of these domain pairs. Modest boostrap values were a consequence of the short, 33-aa sequence length and the triangle fans represent 100+ species orthologs for each MTBD category. e The influence of extreme cold adaptation on MAPT in the Antarctic rockcod Notothenia coriiceps was determined by reconstructing the transcript and deduced protein sequence from the corresponding genome assembly (gb:KL666590.1). The results showed 7 sequential MTBDs identified by their match score E-value to individual pHMMs (B above) with a 4-fold tandem duplication of MTBD 2 containing the typical central Cys preceded by an aa replacement from Lys to Arg