Arabidopsis homolog of the yeast TREX-2 mRNA export complex: components and anchoring nucleoporin.
Nuclear pore complexes (NPCs) are vital to nuclear-cytoplasmic communication in eukaryotes. The yeast NPC-associated TREX-2 complex, also known as the Thp1-Sac3-Cdc31-Sus1 complex, is anchored on the NPC via the nucleoporin Nup1, and is essential for mRNA export. Here we report the identification and characterization of the putative Arabidopsis thaliana TREX-2 complex and its anchoring nucleoporin. Physical and functional evidence support the identification of the Arabidopsis orthologs of yeast Thp1 and Nup1. Of three Arabidopsis homologs of yeast Sac3, two are putative TREX-2 components, but, surprisingly, none are required for mRNA export as they are in yeast. Physical association of the two Cdc31 homologs, but not the Sus1 homolog, with the TREX-2 complex was observed. In addition to identification of these TREX-2 components, direct interactions of the Arabidopsis homolog of DSS1, which is an established proteasome component in yeast and animals, with both the TREX-2 complex and the proteasome were observed. This suggests the possibility of a link between the two complexes. Thus this work has identified the putative Arabidopsis TREX-2 complex and provides a foundation for future studies of nuclear export in Arabidopsis.
Lu
Qing
Q
Agriculture and Agri-Food Canada, Southern Crop Protection and Food Research Centre, London, ON N5V 4T3, Canada.
Tang
Xurong
X
Tian
Gang
G
Wang
Fang
F
Liu
Kede
K
Nguyen
Vi
V
Kohalmi
Susanne E
SE
Keller
Wilfred A
WA
Tsang
Edward W T
EW
Harada
John J
JJ
Rothstein
Steven J
SJ
Cui
Yuhai
Y
D021581:Active Transport, Cell Nucleus; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D009154:Mutation; D022022:Nuclear Pore / Q000378:metabolism*; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D030821:Plants, Genetically Modified; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D011485:Protein Binding; D034443:RNA Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D020798:Two-Hybrid System Techniques
D029681:Arabidopsis Proteins; D008164:Luminescent Proteins; D028861:Nuclear Pore Complex Proteins; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D046988:Proteasome Endopeptidase Complex