PDBsum entry 4xiz

Lipid transport/oxidoreductase

PDB id: 4xiz

Contents

Protein chains

170 a.a.

70 a.a.

Ligands

LPP ×2

Waters ×380

PDB id:

4xiz

Name:

Lipid transport/oxidoreductase

Title:

Structure of a phospholipid trafficking complex with substrate

Structure:

Protein ups1, mitochondrial. Chain: a, b. Synonym: unprocessed mgm1 protein 1. Engineered: yes. Mitochondrial distribution and morphology protein 35. Chain: m, n. Fragment: unp residues 6-75. Engineered: yes

Source:

Saccharomyces cerevisiae (strain atcc 204508 / s288c). Baker's yeast. Organism_taxid: 559292. Strain: atcc 204508 / s288c. Gene: ups1, ylr193c. Expressed in: escherichia coli. Expression_system_taxid: 562. Gene: mdm35, ykl053c-a.

Resolution:

2.00Å R-factor: 0.202 R-free: 0.240

Authors:

F.Yu,F.He,C.Wang,P.Zhang

Key ref:

F.Yu et al. (2015). Structural basis of intramitochondrial phosphatidic acid transport mediated by Ups1-Mdm35 complex. Embo Rep, 16, 813-823. PubMed id: 26071601 DOI: 10.15252/embr.201540137

Date:

08-Jan-15 Release date: 01-Jul-15

Protein chains

Q05776  (UPS1_YEAST) -  Protein UPS1, mitochondrial from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 175 a.a.

Struc: 170 a.a.

Protein chains

O60200  (MDM35_YEAST) -  Mitochondrial distribution and morphology protein 35 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 86 a.a.

Struc: 70 a.a.

DOI no: 10.15252/embr.201540137

Embo Rep 16:813-823 (2015)

PubMed id: 26071601

Structural basis of intramitochondrial phosphatidic acid transport mediated by Ups1-Mdm35 complex.

F.Yu, F.He, H.Yao, C.Wang, J.Wang, J.Li, X.Qi, H.Xue, J.Ding, P.Zhang.

ABSTRACT

Ups1 forms a complex with Mdm35 and is critical for the transport of phosphatidic acid (PA) from the mitochondrial outer membrane to the inner membrane. We report the crystal structure of the Ups1-Mdm35-PA complex and the functional characterization of Ups1-Mdm35 in PA binding and transfer. Ups1 features a barrel-like structure consisting of an antiparallel β-sheet and three α-helices. Mdm35 adopts a three-helical clamp-like structure to wrap around Ups1 to form a stable complex. The β-sheet and α-helices of Ups1 form a long tunnel-like pocket to accommodate the substrate PA, and a short helix α2 acts as a lid to cover the pocket. The hydrophobic residues lining the pocket and helix α2 are critical for PA binding and transfer. In addition, a hydrophilic patch on the surface of Ups1 near the PA phosphate-binding site also plays an important role in the function of Ups1-Mdm35. Our study reveals the molecular basis of the function of Ups1-Mdm35 and sheds new light on the mechanism of intramitochondrial phospholipid transport by the MSF1/PRELI family proteins.