PDBsum entry 1jhs

Gene regulation

PDB id: 1jhs

Contents

Protein chain

188 a.a. *

Waters ×196

* Residue conservation analysis

PDB id:

1jhs

Name:

Gene regulation

Title:

Protein mog1 e65a mutant

Structure:

Mog1 protein. Chain: a. Synonym: mog1p, nuclear protein that interacts with gtp-gsp1p, hypothetical protein yjr074w. Engineered: yes. Mutation: yes

Source:

Saccharomyces cerevisiae. Baker's yeast. Organism_taxid: 4932. Gene: mog1. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

1.90Å R-factor: 0.208 R-free: 0.248

Authors:

R.P.Baker,M.T.Harreman,J.F.Ecclestone,A.H.Corbett,M.Stewart

Key ref:

R.P.Baker et al. (2001). Interaction between Ran and Mog1 is required for efficient nuclear protein import. J Biol Chem, 276, 41255-41262. PubMed id: 11509570 DOI: 10.1074/jbc.M106060200

Date:

28-Jun-01 Release date: 03-Jun-03

Protein chain

P47123  (MOG1_YEAST) -  Nuclear import protein MOG1 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 218 a.a.

Struc: 188 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1074/jbc.M106060200

J Biol Chem 276:41255-41262 (2001)

PubMed id: 11509570

Interaction between Ran and Mog1 is required for efficient nuclear protein import.

R.P.Baker, M.T.Harreman, J.F.Eccleston, A.H.Corbett, M.Stewart.

ABSTRACT

Mog1 is a nuclear protein that interacts with Ran, the Ras family GTPase that confers directionality to nuclear import and export pathways. Deletion of MOG1 in Saccharomyces cerevisiae (Deltamog1) causes temperature-sensitive growth and defects in nuclear protein import. Mog1 has previously been shown to stimulate GTP release from Ran and we demonstrate here that addition of Mog1 to either Ran-GTP or Ran-GDP results in nucleotide release and formation of a stable complex between Mog1 and nucleotide-free Ran. Moreover, MOG1 shows synthetic lethality with PRP20, the Ran guanine nucleotide exchange factor (RanGEF) that also binds nucleotide-free Ran. To probe the functional role of the Mog1-Ran interaction, we engineered mutants of yeast Mog1 and Ran that specifically disrupt their interaction both in vitro and in vivo. These mutants indicate that the interaction interface involves conserved Mog1p residues Asp(62) and Glu(65), and residue Lys(136) in yeast Ran. Mutations at these residues decrease the ability of Mog1 to bind and release nucleotide from Ran. Furthermore, the E65K-Mog1 and K136E-Ran mutations in yeast cause temperature sensitivity and mislocalization of a nuclear import reporter protein, similar to the phenotype observed for the Deltamog1 strain. Our results indicate that a primary function of Mog1 requires binding to Ran and that the Mog1-Ran interaction is necessary for efficient nuclear protein import in vivo.

Selected figure(s)

Figure 4.
Fig. 4. Identification of a putative Mog1-binding site on Ran. A, His-tagged human Mog1 immobilized on Ni-NTA-agarose was assayed for binding to wild-type vertebrate Ran, T42A, Q69L, F72W, or R76E charged with GDP or GTP. As a control, GDP-bound wild-type Ran and mutants were also assayed for binding to NTF2-Sepharose beads. B, schematic representation of the Ran-GDP structure showing the positions of residues targeted for mutagenesis. Lys134 of Ran (red), located on helix 4 (dark pink) is equivalent to Lys136 in Gsp1p, which is required for efficient Mog1p binding. Mutation of two residues (green) decrease binding of Gsp1p to Ntf2p without affecting the Mog1-Ran interaction. The positions of the switch I loop (yellow), switch II loop (orange), and guanine nucleotide (indigo) are indicated. Conserved residues Lys123 and Asp125 (violet) stabilize binding of the guanine base. The COOH-terminal helix 6 (light pink) packs against helix 4 in the Ran-GDP structure.

Figure 7.
Fig. 7. mog1 and prp20-1 mutants are synthetically lethal. The mog1 and prp20-1 mutants were combined by deleting the MOG1 gene in a prp20-1 background as described under "Experimental Procedures." The double mutant cells were maintained by a PRP20 plasmid. The growth of prp20-1 mog1 was compared when transformed with both PRP20 and MOG1 (wild-type), MOG1 (prp20-1), PRP20 ( mog1), or empty vector (prp20-1 mog1). For analysis of the double mutant, the wild-type PRP20 maintenance plasmid was expelled using 5-fluoroorotic acid. Cells were grown to saturation in synthetic media before serial dilution (1:10) and spotting. The plate was incubated at 25 °C for 5 days. The wild-type, mog1, and prp20-1 cells all grow at similar rates. prp20-1 mog1 cells are unable to grow, demonstrating a synthetic lethal interaction between these two mutations.

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2001, 276, 41255-41262) copyright 2001.

Figures were selected by an automated process.