Biology subjects

Tateishi, Y.

Publications and source records attributed to Tateishi, Y..

2 recordsLinked to original sources

bioRxiv2024

Global distribution of a land plant by means of oceanic dispersal

The geographic range of species is one of the key indicators of their evolutionary success. Unlike animals, most plants are immobile and expand their range primarily through long-distance dispersal (LDD) of seeds. Seeds can be dispersed over very long distances, especially by ocean currents. However, little is understood about the role of ocean currents in LDD and the contribution of land barriers to genetic differentiation on a global scale. To investigate the outermost limits of LDD by ocean currents in land plants, we studied Canavalia rosea (Sw.) DC. (Fabaceae), which is distributed throughout littoral areas of the tropics and subtropics around the world. Our results using DNA sequences from six chloroplast regions and two low-copy nuclear loci from 436 individuals in 37 populations revealed that ocean currents played a crucial role in the species range expansion and maintaining its global distribution despite the constraints by continental barriers. These suggest that the global distribution of C. rosea is the result of recent transoceanic dispersal within and between the Atlantic and Indo-Pacific oceans, while the Isthmus of Panama has prevented gene flow across the American continents. These results highlight the power of oceanic seed dispersal in shaping plant biogeography.

evolutionary biology↗

bioRxiv2021

Multi-state structure determination and dynamics analysis reveals a new ubiquitin-recognition mechanism in yeast ubiquitin C-terminal hydrolase

Despite accumulating evidence that protein dynamics is indispensable for understanding the structural basis of biological activities, it remains challenging to visualize the spatial description of the dynamics and to associate transient conformations with their molecular functions. We have developed a new NMR protein structure determination method for the inference of multi-state conformations using multiple types of NMR data, including paramagnetic NMR and residual dipolar couplings, as well as conventional NOEs. Integration of these data in the structure calculation permits delineating accurate ensemble structures of biomacromolecules. Applying the method to the protein yeast ubiquitin hydrolase 1 (YUH1), we find large dynamics of its N-terminus and crossover loop surrounding the active site for ubiquitin-recognition and proteolysis. The N-terminus gets into and out of the crossover loop, suggesting their underlying functional significance. Our results, including those from biochemical analysis, show that large motion surrounding the active site contributes strongly to the efficiency of the enzymatic activity.

biophysics↗