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Cryo-EM structure of full-length human immunoglobulin M

ABSTRACT:

SUBMITTER: Peter Rosenthal

PROVIDER: EMPIAR-11077 | biostudies-other |

REPOSITORIES: biostudies-other

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Cryomicroscopy reveals the structural basis for a flexible hinge motion in the immunoglobulin M pentamer.

Chen Qu Q Menon Rajesh R Calder Lesley J LJ Tolar Pavel P Rosenthal Peter B PB

Nature communications 20221023 1

Immunoglobulin M (IgM) is the most ancient of the five isotypes of immunoglobulin (Ig) molecules and serves as the first line of defence against pathogens. Here, we use cryo-EM to image the structure of the human full-length IgM pentamer, revealing antigen binding domains flexibly attached to the asymmetric and rigid core formed by the Cμ4 and Cμ3 constant regions and the J-chain. A hinge is located at the Cμ3/Cμ2 domain interface, allowing Fabs and Cμ2 to pivot as a unit both in-plane and out-o ...[more]

PMID: 36274064

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