| Structural highlights
Function
DXS_ARATH Catalyzes the acyloin condensation reaction between C atoms 2 and 3 of pyruvate and glyceraldehyde 3-phosphate to yield 1-deoxy-D-xylulose-5-phosphate (DXP). Is a limiting enzyme for plastidic isoprenoid biosynthesis and essential for chloroplast development.[1] [2] [3]
Publication Abstract from PubMed
Small heat shock proteins (sHsps) bind unfolding proteins, thereby playing a pivotal role in the maintenance of proteostasis in virtually all living organisms. Structural elucidation of sHsp-substrate complexes has been hampered by the transient and heterogeneous nature of their interactions, and the precise mechanisms underlying substrate recognition, promiscuity, and chaperone activity of sHsps remain unclear. Here we show the formation of a stable complex between Arabidopsis thaliana plastid sHsp, Hsp21, and its natural substrate 1-deoxy-D-xylulose 5-phosphate synthase (DXPS) under heat stress, and report cryo-electron microscopy structures of Hsp21, DXPS and Hsp21-DXPS complex at near-atomic resolution. Monomeric Hsp21 binds across the dimer interface of DXPS and engages in multivalent interactions by recognizing highly dynamic structural elements in DXPS. Hsp21 partly unfolds its central alpha-crystallin domain to facilitate binding of DXPS, which preserves a native-like structure. This mode of interaction suggests a mechanism of sHsps anti-aggregation activity towards a broad range of substrates.
Structural basis of substrate recognition and thermal protection by a small heat shock protein.,Yu C, Leung SKP, Zhang W, Lai LTF, Chan YK, Wong MC, Benlekbir S, Cui Y, Jiang L, Lau WCY Nat Commun. 2021 May 21;12(1):3007. doi: 10.1038/s41467-021-23338-y. PMID:34021140[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Estévez JM, Cantero A, Romero C, Kawaide H, Jiménez LF, Kuzuyama T, Seto H, Kamiya Y, León P. Analysis of the expression of CLA1, a gene that encodes the 1-deoxyxylulose 5-phosphate synthase of the 2-C-methyl-D-erythritol-4-phosphate pathway in Arabidopsis. Plant Physiol. 2000 Sep;124(1):95-104. PMID:10982425 doi:10.1104/pp.124.1.95
- ↑ Estévez JM, Cantero A, Reindl A, Reichler S, León P. 1-Deoxy-D-xylulose-5-phosphate synthase, a limiting enzyme for plastidic isoprenoid biosynthesis in plants. J Biol Chem. 2001 Jun 22;276(25):22901-9. PMID:11264287 doi:10.1074/jbc.M100854200
- ↑ Mandel MA, Feldmann KA, Herrera-Estrella L, Rocha-Sosa M, León P. CLA1, a novel gene required for chloroplast development, is highly conserved in evolution. Plant J. 1996 May;9(5):649-58. PMID:8653115 doi:10.1046/j.1365-313x.1996.9050649.x
- ↑ Yu C, Leung SKP, Zhang W, Lai LTF, Chan YK, Wong MC, Benlekbir S, Cui Y, Jiang L, Lau WCY. Structural basis of substrate recognition and thermal protection by a small heat shock protein. Nat Commun. 2021 May 21;12(1):3007. doi: 10.1038/s41467-021-23338-y. PMID:34021140 doi:http://dx.doi.org/10.1038/s41467-021-23338-y
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