George Simos

Yeast Los1p Has Properties of an Exportin-Like Nucleocytoplasmic Transport Factor for tRNA

Hellmuth, Klaus, Lau, Denise M., Bischoff, F. Ralf, Künzler, Markus, Hurt, Ed, Simos, George

Saccharomyces cerevisiae Los1p, which is genetically linked to the nuclear pore protein Nsp1p and several tRNA biogenesis factors, was recently grouped into the family of importin/karyopherin-β-like...

Nuclear mRNA Export Requires Complex Formation between Mex67p and Mtr2p at the Nuclear Pores

Santos-Rosa, Helena, Moreno, Horacio, Simos, George, Segref, Alexandra, Fahrenkrog, Birthe, Panté, Nelly, ...

We have identified between Mex67p and Mtr2p a complex which is essential for mRNA export. This complex, either isolated from yeast or assembled in Escherichia coli, can bind in vitro to RNA through...

Cloning and characterization of the Schizosaccharomyces pombe tRNA:pseudouridine synthase Pus1p

Hellmuth, Klaus, Grosjean, Henri, Motorin, Yuri, Deinert, Karina, Hurt, Ed, Simos, George

Saccharomyces cerevisiae cells that carry deletions in both the LOS1 (a tRNA export receptor) and the PUS1 (a tRNA:pseudouridine synthase) genes exhibit a thermosensitive growth defect. A...

The intracellular location of two aminoacyl-tRNA synthetases depends on complex formation with Arc1p

Galani, Kyriaki, Großhans, Helge, Deinert, Karina, Hurt, Eduard C., Simos, George

In yeast, two aminoacyl-tRNA synthetases, MetRS and GluRS, are associated with Arc1p. We have studied the mechanism of this complex formation and found that the non-catalytic N-terminally appended...

An aminoacylation-dependent nuclear tRNA export pathway in yeast

Grosshans, Helge, Hurt, Ed, Simos, George

Yeast Los1p, the homolog of human exportin-t, mediates nuclear export of tRNA. Using fluorescence in situ hybridization, we could show that the export of some intronless tRNA species is not...

Structural basis of yeast aminoacyl-tRNA synthetase complex formation revealed by crystal structures of two binary sub-complexes

Simader, Hannes, Hothorn, Michael, Köhler, Christine, Basquin, Jerome, Simos, George, Suck, Dietrich

The yeast aminoacyl-tRNA synthetase (aaRS) complex is formed by the methionyl- and glutamyl-tRNA synthetases (MetRS and GluRS, respectively) and the tRNA aminoacylation cofactor Arc1p. It is...

Yeast Los1p Has Properties of an Exportin-Like Nucleocytoplasmic Transport Factor for tRNA

Hellmuth, Klaus, Lau, Denise M., Bischoff, F. Ralf, Künzler, Markus, Hurt, Ed, Simos, George

Saccharomyces cerevisiae Los1p, which is genetically linked to the nuclear pore protein Nsp1p and several tRNA biogenesis factors, was recently grouped into the family of importin/karyopherin-β-like...

Nuclear mRNA Export Requires Complex Formation between Mex67p and Mtr2p at the Nuclear Pores

Santos-Rosa, Helena, Moreno, Horacio, Simos, George, Segref, Alexandra, Fahrenkrog, Birthe, Panté, Nelly, ...

We have identified between Mex67p and Mtr2p a complex which is essential for mRNA export. This complex, either isolated from yeast or assembled in Escherichia coli, can bind in vitro to RNA through...

Cloning and characterization of the Schizosaccharomyces pombe tRNA:pseudouridine synthase Pus1p

Hellmuth, Klaus, Grosjean, Henri, Motorin, Yuri, Deinert, Karina, Hurt, Ed, Simos, George

Saccharomyces cerevisiae cells that carry deletions in both the LOS1 (a tRNA export receptor) and the PUS1 (a tRNA:pseudouridine synthase) genes exhibit a thermosensitive growth defect. A...

The intracellular location of two aminoacyl-tRNA synthetases depends on complex formation with Arc1p

Galani, Kyriaki, Großhans, Helge, Deinert, Karina, Hurt, Eduard C., Simos, George

In yeast, two aminoacyl-tRNA synthetases, MetRS and GluRS, are associated with Arc1p. We have studied the mechanism of this complex formation and found that the non-catalytic N-terminally appended...

An aminoacylation-dependent nuclear tRNA export pathway in yeast

Grosshans, Helge, Hurt, Ed, Simos, George

Yeast Los1p, the homolog of human exportin-t, mediates nuclear export of tRNA. Using fluorescence in situ hybridization, we could show that the export of some intronless tRNA species is not...

Structural basis of yeast aminoacyl-tRNA synthetase complex formation revealed by crystal structures of two binary sub-complexes

Simader, Hannes, Hothorn, Michael, Köhler, Christine, Basquin, Jerome, Simos, George, Suck, Dietrich

The yeast aminoacyl-tRNA synthetase (aaRS) complex is formed by the methionyl- and glutamyl-tRNA synthetases (MetRS and GluRS, respectively) and the tRNA aminoacylation cofactor Arc1p. It is...

A Novel In Vivo Assay Reveals Inhibition of Ribosomal Nuclear Export in Ran-Cycle and Nucleoporin Mutants

Hurt, Ed, Hannus, Stefan, Schmelzl, Birgit, Lau, Denise, Tollervey, David, Simos, George

To identify components involved in the nuclear export of ribosomes in yeast, we developed an in vivo assay exploiting a green fluorescent protein (GFP)-tagged version of ribosomal protein L25. After...

Biogenesis of the Signal Recognition Particle (Srp) Involves Import of Srp Proteins into the Nucleolus, Assembly with the Srp-Rna, and Xpo1p-Mediated Export

Grosshans, Helge, Deinert, Karina, Hurt, Ed, Simos, George

The signal recognition particle (SRP) targets nascent secretory proteins to the ER, but how and where the SRP assembles is largely unknown. Here we analyze the biogenesis of yeast SRP, which consists...