6X0B

Crystal Structure of Thioredoxin NaTrxh from Nicotiana alata

Summary for 6X0B

• Entry DOI: 10.2210/pdb6x0b/pdb
• Descriptor: Thioredoxin H, 1,2-ETHANEDIOL (3 entities in total)
• Functional Keywords: natrxh, thioredoxin h, s-rnase, self-incompatibility, oxidoreductase
• Biological source: Nicotiana alata (Winged tobacco)
• Total number of polymer chains: 2
• Total formula weight: 33764.56

Authors

Gonzalez-Segura, L.,Torres-Rodriguez, M.D.,Cruz-Garcia, F. (deposition date: 2020-05-15, release date: 2020-07-22, Last modification date: 2023-10-18)

Primary citation

Torres-Rodriguez, M.D.,Gonzalez-Segura, L.,Rodriguez-Sotres, R.,Juarez-DiaZ, J.A.,Cruz-Zamora, Y.,Cruz-Garcia, F.
High resolution crystal structure of NaTrxh from Nicotiana alata and its interaction with the S-RNase.
J.Struct.Biol., 212:107578-107578, 2020

PubMed Abstract: Thioredoxins are regulatory proteins that reduce disulfide bonds on target proteins. NaTrxh, which belongs to the plant thioredoxin family h subgroup 2, interacts and reduces the S-RNase enhancing its ribonuclease activity seven-fold, resulting an essential protein for pollen rejection inNicotiana.Here, the crystal structure of NaTrxh at 1.7 Å by X-ray diffraction is reported. NaTrxh conserves the typical fold observed in other thioredoxins from prokaryotes and eukaryotes, but it contains extensions towards both N- and C-termini.The NaTrxh N-terminal extension participates in the reduction of S-RNase, and in the structure reported here, this is orientated towards the reactive site. The interaction between S-RNase and the NaTrxh N-terminal was simulated and the short-lived complex observed lasted for a tenth of ns. Moreover, we identified certain amino acids as S-RNase-E155 and NaTrxh-M104 as good candidates to contribute to the stability of the complex. Furthermore, we simulated the reduction of the C153-C186 S-RNase disulfide bond and observed subtle changes that affect the entire core, which might explain the increase in the ribonuclease activity of S-RNase when it is reduced by NaTrxh.

PubMed: 32682729
DOI: 10.1016/j.jsb.2020.107578

Experimental method

X-RAY DIFFRACTION (1.702 Å)