Genomic and structural insights into TATA-Binding protein from cestodes.

Abstract

The TATA-binding protein (TBP) is an essential component of the eukaryotic transcriptional machinery, yet little is known about the structure, evolution, and functional divergence of TBP paralogs in parasitic flatworms. Here, we performed a comprehensive comparative analysis of TBP1 and TBP2 across cestode species of medical and veterinary relevance. Using genomic annotation, multiple sequence alignment, homology modeling, phylogenetics, electrostatic potential mapping, and protein - DNA docking complemented with molecular dynamics (MD) simulations, we reveal that both paralogs maintain a highly conserved genomic organization and the canonical TBP α/β saddle architecture. TBP1 exhibits moderate variability in sequence and electrostatic in peripheral regions, whereas TBP2 is more conserved, suggesting distinct evolutionary constraints. Despite paralog divergence, all cestode TBPs retain the key aromatic and basic residues required for minor-groove recognition of the TATA box and interaction with general transcription factors. Docking and MD simulations confirm a conserved pattern of TATA-binding across species, with TBP2 displaying exceptionally uniform interaction networks. Together, these findings provide genomic and structural data for TBPs in cestodes, suggesting the existence of paralog-specific regulatory roles and offering new insights into transcriptional control in parasitic flatworms.