A Putative New Role of Tv-PSP1 Recognizes IRE and ERE Hairpin Structures from <i>Trichomonas vaginalis</i>
César Millán-Pacheco,
Rodrigo Arreola,
Alma Villalobos-Osnaya,
Georgina Garza-Ramos,
Iris N. Serratos,
Adelaida Díaz-Vilchis,
Enrique Rudiño-Piñera,
María Elizbeth Alvarez-Sanchez
Affiliations
César Millán-Pacheco
Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
Rodrigo Arreola
Psychiatric Genetics Department, Clinical Research Branch, National Institute of Psychiatry, Ramón de la Fuente, Calzada. México-Xochimilco 101, Colonia San Lorenzo Huipulco, Tlalpan, México City 14370, Mexico
Alma Villalobos-Osnaya
Posgrado en Ciencias Genómicas, Universidad Autónoma de la Ciudad de México (UACM), San Lorenzo # 290, Col. Del Valle, Ciudad de Mexico 03100, Mexico
Georgina Garza-Ramos
Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Universidad # 3000, Ciudad de Mexico 04510, Mexico
Iris N. Serratos
Departamento de Química, Universidad Autónoma Metropolitana, Iztapalapa, Ciudad de Mexico 09340, Mexico
Adelaida Díaz-Vilchis
Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Cuernavaca 62210, Mexico
Enrique Rudiño-Piñera
Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Cuernavaca 62210, Mexico
María Elizbeth Alvarez-Sanchez
Posgrado en Ciencias Genómicas, Universidad Autónoma de la Ciudad de México (UACM), San Lorenzo # 290, Col. Del Valle, Ciudad de Mexico 03100, Mexico
To understand whether protein Tv-PSP1 from Trichomonas vaginalis recognizes mRNA parasite stem-loop structures, we conducted REMSA and intrinsic fluorescence assays. We found the recombinant Tv-PSP1 structure, determined with X-ray crystallography, showed unusual thermal stability of the quaternary structure, associated with a disulfide bridge CYS76-CYS104. To gain deeper insight into the Tv-PSP1 interaction with mRNA stem-loops (mRNAsl) and its relationship with thermal stability, we also used an integrated computational protocol that combined molecular dynamics simulations, docking assays, and binding energy calculations. Docking models allowed us to determine a putative contact surface interaction region between Tv-PSP1 and mRNAsl. We determined the contributions of these complexes to the binding free energy (ΔGb) in the electrostatic (ΔGelec) and nonelectrostatic (ΔGnon-elec) components using the Adaptive Poisson–Boltzmann Solver (APBS) program. We are the first, to the best of our knowledge, to show the interaction between Tv-PSP1 and the stem-loop structures of mRNA.
