Biophysical characterization of the myosin XI-K Cargo-Binding Domain from Arabidopsis thaliana.

V TUROWSKI; D RUIZ; A NASCIMENTO; M MURAKAMI

Dresden

Congreso; 10th European Biophysics Congress (EBSA 2015); 2015

European Biophysical Societies' Association (EBSA)

The unconventional myosins play an important role in several physiological processes such as intracellular traffic of organelles, cytoplasmic streaming, cellular shape, signal transduction and morphogenesis. Functional diversity for these molecular motors resides in the variability of their C-terminal domains. In plants, class XI myosins have a C-terminal Cargo-Binding Domain (CBD), which is critical to their interaction with vesicles, organelles and other molecular targets. In the last years there were great efforts to elucidate the physiological functions of plant myosins XI; however, little is known about structural features of them. In this study, we have performed an extensive biophysical characterization (DSL, CD, DSF and SAXS) of a plant CBD from Arabidopsis myosin XI-K. Altogether, these results underline that the CBD from AtMyoXI-K has an alpha-helical domain architecture with an elongated shape, which is similar to that observed for myosins V from yeast to human, indicating a close functional correlation between MyoVs and plant MyoXIs. These findings highlight the high conservation degree of these molecular motors among the living kingdoms and their importance for life maintenance in eukaryotes.