2H4Q

Crystal structure of a M-loop deletion variant of MENT in the cleaved conformation

Summary for 2H4Q

• Entry DOI: 10.2210/pdb2h4q/pdb
• Related: 2H4P 2H4R 2H4S
• Descriptor: Heterochromatin-associated protein MENT (3 entities in total)
• Functional Keywords: serine protease inhibitor, serpin, hydrolase inhibitor
• Biological source: Gallus gallus (chicken); More
• Cellular location: Nucleus: O73790 O73790
• Total number of polymer chains: 2
• Total formula weight: 48139.16

Authors

Whisstock, J.C.,Buckle, A.M.,McGowan, S.,Irving, J.A. (deposition date: 2006-05-25, release date: 2006-07-18, Last modification date: 2023-10-25)

Primary citation

McGowan, S.,Buckle, A.M.,Irving, J.A.,Ong, P.C.,Bashtannyk-Puhalovich, T.A.,Kan, W.T.,Henderson, K.N.,Bulynko, Y.A.,Popova, E.Y.,Smith, A.I.,Bottomley, S.P.,Rossjohn, J.,Grigoryev, S.A.,Pike, R.N.,Whisstock, J.C.
X-ray crystal structure of MENT: evidence for functional loop-sheet polymers in chromatin condensation.
Embo J., 25:3144-3155, 2006

PubMed Abstract: Most serpins are associated with protease inhibition, and their ability to form loop-sheet polymers is linked to conformational disease and the human serpinopathies. Here we describe the structural and functional dissection of how a unique serpin, the non-histone architectural protein, MENT (Myeloid and Erythroid Nuclear Termination stage-specific protein), participates in DNA and chromatin condensation. Our data suggest that MENT contains at least two distinct DNA-binding sites, consistent with its simultaneous binding to the two closely juxtaposed linker DNA segments on a nucleosome. Remarkably, our studies suggest that the reactive centre loop, a region of the MENT molecule essential for chromatin bridging in vivo and in vitro, is able to mediate formation of a loop-sheet oligomer. These data provide mechanistic insight into chromatin compaction by a non-histone architectural protein and suggest how the structural plasticity of serpins has adapted to mediate physiological, rather than pathogenic, loop-sheet linkages.

PubMed: 16810322
DOI: 10.1038/sj.emboj.7601201

Experimental method

X-RAY DIFFRACTION (2.1 Å)