Structural similarity in the absence of sequence homology of the messenger RNA export factors Mtr2 and p15.
The association between Mtr2 and Mex67 is essential for the nuclear export of bulk messenger RNA in yeast. In metazoans, the analogous function is carried out by the TAP-p15 heterodimer. Whereas Mex67 and TAP are highly conserved proteins, their binding partners, Mtr2 and p15, share no sequence similarity, but are nevertheless functionally homologous. Here, we report the 2.8-A resolution crystal structure of Mtr2 in complex with the NTF2-like domain of Mex67. Mtr2 is a novel member of the NTF2-like family and interacts with Mex67, forming a complex with a similar structural architecture to that of TAP-p15. Mtr2 fulfils an analogous function to that of human p15 in maintaining the structural integrity of the heterodimer. In addition, Mtr2 presents a long internal loop, which contains residues that affect the export of the large ribosomal subunit.
Fribourg
Sébastien
S
European Molecular Biology Laboratory, Meyerhofstrasse 1, D-69117 Heidelberg, Germany.
Conti
Elena
E
D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D019281:Dimerization; D026901:Membrane Transport Proteins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism; D029543:Nucleocytoplasmic Transport Proteins / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D034443:RNA Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000378:metabolism; D017385:Sequence Homology
D002352:Carrier Proteins; C106898:MEX67 protein, S cerevisiae; D026901:Membrane Transport Proteins; C480169:Mtr2 protein, S cerevisiae; D009687:Nuclear Proteins; D029543:Nucleocytoplasmic Transport Proteins; C503613:Nutf2 protein, mouse; C402484:Nxt1 protein, mouse; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins