5XA5

Crystal structure of HMP-1-HMP-2 complex

Summary for 5XA5

• Entry DOI: 10.2210/pdb5xa5/pdb
• Descriptor: Alpha-catenin-like protein hmp-1, Beta-catenin-like protein hmp-2 (3 entities in total)
• Functional Keywords: five-helix bundle, cell adhesion
• Biological source: Caenorhabditis elegans; More
• Total number of polymer chains: 2
• Total formula weight: 35984.40

Authors

Shao, X.,Kang, H.,Weis, W.I.,Hardin, J.,Choi, H.J. (deposition date: 2017-03-11, release date: 2017-08-30, Last modification date: 2024-03-27)

Primary citation

Shao, X.,Kang, H.,Loveless, T.,Lee, G.R.,Seok, C.,Weis, W.I.,Choi, H.J.,Hardin, J.
Cell-cell adhesion in metazoans relies on evolutionarily conserved features of the alpha-catenin· beta-catenin-binding interface.
J.Biol.Chem., 292:16477-16490, 2017

PubMed Abstract: Stable tissue integrity during embryonic development relies on the function of the cadherin·catenin complex (CCC). The CCC is a useful paradigm for analyzing requirements for specific interactions among the core components of the CCC, and it provides a unique opportunity to examine evolutionarily conserved mechanisms that govern the interaction between α- and β-catenin. HMP-1, unlike its mammalian homolog α-catenin, is constitutively monomeric, and its binding affinity for HMP-2/β-catenin is higher than that of α-catenin for β-catenin. A crystal structure shows that the HMP-1·HMP-2 complex forms a five-helical bundle structure distinct from the structure of the mammalian α-catenin·β-catenin complex. Deletion analysis based on the crystal structure shows that the first helix of HMP-1 is necessary for binding HMP-2 avidly and for efficient recruitment of HMP-1 to adherens junctions in embryos. HMP-2 Ser-47 and Tyr-69 flank its binding interface with HMP-1, and we show that phosphomimetic mutations at these two sites decrease binding affinity of HMP-1 to HMP-2 by 40-100-fold experiments using HMP-2 S47E and Y69E mutants showed that they are unable to rescue () mutants, suggesting that phosphorylation of HMP-2 on Ser-47 and Tyr-69 could be important for regulating CCC formation in Our data provide novel insights into how cadherin-dependent cell-cell adhesion is modulated in metazoans by conserved elements as well as features unique to specific organisms.

PubMed: 28842483
DOI: 10.1074/jbc.M117.795567

Experimental method

X-RAY DIFFRACTION (1.6 Å)