In silico prediction of three-dimensional structure and interactome analysis of Tubulin α subfamily of Arabidopsis thaliana

Abstract

Microtubules are essential components of cytoskeleton, rigid hollow rods approximately 25 nm in diameter. Microtubules are dynamic structures being continuously assembled and disassembled within the cell. The basic building blocks of microtubules are heterodimers of globular α- and β-tubulin subunits In Arabidopsis thaliana tubulin subunits are encoded by small gene families, six for α-tubulin and nine for β-tubulin.Both α- and β-tubulin bind GTP, which functions analogously to the ATP bound to actin to regulate polymerization. It is shown that tubulin α forms hydrogen bonds with the GTPase domain of b-tubulin. Multiple sequence alignment revealed high similarity between the family subunits. Due to the missing of three dimensional structuresin A. thaliana, structural models were predicted and validated. Additionally, protein domains search revealed that all tubulin α family subunits contain GTPase domain as the tubulin C terminal domain, confirming previous research. Finally the interactome analysis revealed several interactomes. AtTUA6 shows strong interaction with embryosac development arrest 10 protein (EDA10), involved in stimulating the exchange of guanyl nucleotides, enabling the replacement of GDP by GTP in association with a GTPases.

Keywords

• 3D structure
• interactome
• microtubules
• tubulin α
• functional annotation