Crystal Structure of UDP-Glc/GlcNAc 4-Epimerase with NAD/UDP-GlcNAc

Experimental Data Snapshot

  • Resolution: 2.15 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.197 
  • R-Value Observed: 0.200 

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A maize epimerase modulates cell wall synthesis and glycosylation during stomatal morphogenesis.

Zhou, Y.Zhang, T.Wang, X.Wu, W.Xing, J.Li, Z.Qiao, X.Zhang, C.Wang, X.Wang, G.Li, W.Bai, S.Li, Z.Suo, Y.Wang, J.Niu, Y.Zhang, J.Lan, C.Hu, Z.Li, B.Zhang, X.Wang, W.Galbraith, D.W.Chen, Y.Guo, S.Song, C.P.

(2023) Nat Commun 14: 4384-4384

  • DOI: https://doi.org/10.1038/s41467-023-40013-6
  • Primary Citation of Related Structures:  
    7XPO, 7XPP, 7XPQ

  • PubMed Abstract: 

    The unique dumbbell-shape of grass guard cells (GCs) is controlled by their cell walls which enable their rapid responses to the environment. The molecular mechanisms regulating the synthesis and assembly of GC walls are as yet unknown. Here we have identified BZU3, a maize gene encoding UDP-glucose 4-epimerase that regulates the supply of UDP-glucose during GC wall synthesis. The BZU3 mutation leads to significant decreases in cellular UDP-glucose levels. Immunofluorescence intensities reporting levels of cellulose and mixed-linkage glucans are reduced in the GCs, resulting in impaired local wall thickening. BZU3 also catalyzes the epimerization of UDP-N-acetylgalactosamine to UDP-N-acetylglucosamine, and the BZU3 mutation affects N-glycosylation of proteins that may be involved in cell wall synthesis and signaling. Our results suggest that the spatiotemporal modulation of BZU3 plays a dual role in controlling cell wall synthesis and glycosylation via controlling UDP-glucose/N-acetylglucosamine homeostasis during stomatal morphogenesis. These findings provide insights into the mechanisms controlling formation of the unique morphology of grass stomata.

  • Organizational Affiliation

    State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Jinming avenue 1, Kaifeng, 475004, China.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
UDP-glucose 4-epimerase
A, B
355Zea maysMutation(s): 0 
Gene Names: 542127ZEAMMB73_Zm00001d029151
EC: 5.1.3
Find proteins for C0HI30 (Zea mays)
Explore C0HI30 
Go to UniProtKB:  C0HI30
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupC0HI30
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.15 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.197 
  • R-Value Observed: 0.200 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 65.873α = 90
b = 84.945β = 110.69
c = 73.436γ = 90
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
XDSdata reduction
XDSdata scaling

Structure Validation

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Ligand Structure Quality Assessment 

Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
Ministry of Science and Technology (MoST, China)China--

Revision History  (Full details and data files)

  • Version 1.0: 2023-05-17
    Type: Initial release
  • Version 1.1: 2023-11-29
    Changes: Data collection, Refinement description
  • Version 1.2: 2023-12-06
    Changes: Database references