hingeregionen

Hingeregionen refers to flexible linker regions that connect structural domains within multidomain macromolecules, enabling relative movement and conformational changes essential for function. In proteins, hinge regions are typically located at domain junctions and can act as pivot points during substrate binding, allosteric regulation, or mechanical stress. In the field of immunology, the term is commonly used to describe the hinge region of antibodies, a short, sometimes glycosylated sequence between the Fab and Fc fragments that provides flexibility to the antigen-binding arms.

Chemically, hingeregionen tend to be enriched in glycine and proline and often lack stable secondary structure, existing as disordered segments or adopting transient conformations upon interaction with partners. Their dynamics contribute to allostery, regulate access to active sites, and influence the mechanical properties of proteins and complexes, such as kinases, motor proteins, and extracellular matrix components.

Mutations, post-translational modifications, or alternative splicing affecting hingeregionen can alter domain orientation, stability, or interaction patterns, with potential consequences for activity, signaling, or assembly. Studying hingeregionen employs approaches capable of capturing conformational dynamics, including nuclear magnetic resonance, single-molecule fluorescence resonance energy transfer, cryo-electron microscopy, X-ray crystallography of domain constructs, and small-angle scattering.

Examples include the hinge region of human immunoglobulin G antibodies; the hinge between kinase lobes in protein kinases; and flexible linkers connecting domains in multidomain enzymes.

The term appears in German-language literature as Hingeregionen and is used in broader biochemistry and structural biology to describe these flexible connectors.