3MAL

Crystal structure of the SDF2-like protein from Arabidopsis thaliana

Summary for 3MAL

• Entry DOI: 10.2210/pdb3mal/pdb
• Descriptor: Stromal cell-derived factor 2-like protein, SULFATE ION, 1,2-ETHANEDIOL, ... (4 entities in total)
• Functional Keywords: trefoil fold, mir motifs, unfolded protein response, putative sugar binding protein, plant protein
• Biological source: Arabidopsis thaliana (mouse-ear cress, thale-cress)
• Cellular location: Secreted (Probable): Q93ZE8
• Total number of polymer chains: 2
• Total formula weight: 43983.03

Authors

Ravaud, S.,Radzimanowski, J.,Sinning, I. (deposition date: 2010-03-24, release date: 2010-04-07, Last modification date: 2023-09-06)

Primary citation

Schott, A.,Ravaud, S.,Keller, S.,Radzimanowski, J.,Viotti, C.,Hillmer, S.,Sinning, I.,Strahl, S.
Arabidopsis stromal-derived Factor2 (SDF2) is a crucial target of the unfolded protein response in the endoplasmic reticulum.
J.Biol.Chem., 285:18113-18121, 2010

PubMed Abstract: Stresses increasing the load of unfolded proteins that enter the endoplasmic reticulum (ER) trigger a protective response termed the unfolded protein response (UPR). Stromal cell-derived factor2 (SDF2)-type proteins are highly conserved throughout the plant and animal kingdoms. In this study we have characterized AtSDF2 as crucial component of the UPR in Arabidopsis thaliana. Using a combination of biochemical and cell biological methods, we demonstrate that SDF2 is induced in response to ER stress conditions causing the accumulation of unfolded proteins. Transgenic reporter plants confirmed induction of SDF2 during ER stress. Under normal growth conditions SDF2 is highly expressed in fast growing, differentiating cells and meristematic tissues. The increased production of SDF2 due to ER stress and in tissues that require enhanced protein biosynthesis and secretion, and its association with the ER membrane qualifies SDF2 as a downstream target of the UPR. Determination of the SDF2 three-dimensional crystal structure at 1.95 A resolution revealed the typical beta-trefoil fold with potential carbohydrate binding sites. Hence, SDF2 might be involved in the quality control of glycoproteins. Arabidopsis sdf2 mutants display strong defects and morphological phenotypes during seedling development specifically under ER stress conditions, thus establishing that SDF2-type proteins play a key role in the UPR.

PubMed: 20378538
DOI: 10.1074/jbc.M110.117176

Experimental method

X-RAY DIFFRACTION (1.95 Å)