Upf1p, a highly conserved protein required for nonsense-mediated mRNA decay, interacts with the nuclear pore proteins Nup100p and Nup116p.
Saccharomyces cerevisiae Upf1p is a 971-amino-acid protein that is required for the nonsense-mediated mRNA decay (NMD) pathway, a pathway that degrades mRNAs with premature translational termination codons. We have identified a two-hybrid interaction between Upf1p and the nuclear pore (Nup) proteins, Nup100p and Nup116p. Both nucleoporins predominantly localize to the cytoplasmic side of the nuclear pore and participate in mRNA transport. The two-hybrid interaction between Upf1p and the nuclear pore proteins, Nup100p and Nup116p, is dependent on the presence of the C-terminal 158 amino acids of Upf1p. Nup100p and Nup116p can be co-immunoprecipitated from whole-cell extracts with Upf1p, confirming in vitro the interaction identified by the two-hybrid analysis. Finally, we see a genetic interaction between UPF1 and NUP100. The growth of upf1Delta, can1-100 cells is inhibited by canavanine. The deletion of NUP100 allows upf1Delta, can1-100 cells to grow in the presence of canavanine. Physiologically, the interaction between Upf1p and the nuclear pore proteins, Nup100p and Nup116p, is significant because it suggests a mechanism to ensure that Upf1p associates with newly synthesized mRNA as it is transported from the nucleus to the cytoplasm prior to the pioneer round of translation.
Nazarenus
Tara
T
University of Nebraska-Lincoln, School of Biological Sciences, E146 Beadle Center, Lincoln, Nebraska 68588-0666, USA.
Cedarberg
Rebecca
R
Bell
Ryan
R
Cheatle
Joseph
J
Forch
Amanda
A
Haifley
Alexis
A
Hou
Ann
A
Wanja Kebaara
Bessie
B
Shields
Christina
C
Stoysich
Kate
K
Taylor
Rachel
R
Atkin
Audrey L
AL
D002172:Canavanine / Q000494:pharmacology; D018389:Codon, Nonsense; D004843:Epistasis, Genetic; D017353:Gene Deletion; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism*; D020365:RNA Helicases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D013489:Suppression, Genetic; D020798:Two-Hybrid System Techniques
D018389:Codon, Nonsense; C077731:NUP100 protein, S cerevisiae; C077730:NUP116 protein, S cerevisiae; D028861:Nuclear Pore Complex Proteins; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D002172:Canavanine; C074151:NAM7 protein, S cerevisiae; D020365:RNA Helicases