3B5H

Crystal structure of the extracellular portion of HAb18G/CD147

Summary for 3B5H

• Entry DOI: 10.2210/pdb3b5h/pdb
• Descriptor: Cervical EMMPRIN, ACETATE ION (3 entities in total)
• Functional Keywords: ig-like domain, cell invasion
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 4
• Total formula weight: 80628.83

Authors

Yu, X.-L.,Chen, Z.-N. (deposition date: 2007-10-26, release date: 2008-05-06, Last modification date: 2024-10-30)

Primary citation

Yu, X.L.,Hu, T.,Du, J.M.,Ding, J.P.,Yang, X.M.,Zhang, J.,Yang, B.,Shen, X.,Zhang, Z.,Zhong, W.D.,Wen, N.,Jiang, H.,Zhu, P.,Chen, Z.N.
Crystal structure of HAb18G/CD147: implications for immunoglobulin superfamily homophilic adhesion.
J.Biol.Chem., 283:18056-18065, 2008

PubMed Abstract: CD147, a member of the immunoglobulin superfamily (IgSF), plays fundamental roles in intercellular interactions in numerous pathological and physiological processes. Importantly, our previous studies have demonstrated that HAb18G/CD147 is a novel hepatocellular carcinoma (HCC)-associated antigen, and HAb18G/CD147 stimulates adjacent fibroblasts and HCC cells to produce elevated levels of several matrix metalloproteinases, facilitating invasion and metastasis of HCC cells. In addition, HAb18G/CD147 has also been shown to be a novel universal cancer biomarker for diagnosis and prognostic assessment of a wide range of cancers. However, the structural basis underlying the multifunctional character of CD147 remains unresolved. We report here the crystal structure of the extracellular portion of HAb18G/CD147 at 2.8A resolution. The structure comprises an N-terminal IgC2 domain and a C-terminal IgI domain, which are connected by a 5-residue flexible linker. This unique C2-I domain organization is distinct from those of other IgSF members. Four homophilic dimers exist in the crystal and adopt C2-C2 and C2-I dimerization rather than V-V dimerization commonly found in other IgSF members. This type of homophilic association thus presents a novel model for homophilic interaction between C2 domains of IgSF members. Moreover, the crystal structure of HAb18G/CD147 provides a good structural explanation for the established multifunction of CD147 mediated by homo/hetero-oligomerizations and should represent a general architecture of other CD147 family members.

PubMed: 18430721
DOI: 10.1074/jbc.M802694200

Experimental method

X-RAY DIFFRACTION (2.8 Å)