6z0g
From Proteopedia
Structure of TREM2 transmembrane helix in DPC micelles
Structural highlights
DiseaseTREM2_HUMAN Progressive non-fluent aphasia;Amyotrophic lateral sclerosis;Nasu-Hakola disease;Semantic dementia;Behavioral variant of frontotemporal dementia. The disease is caused by mutations affecting the gene represented in this entry. FunctionTREM2_HUMAN May have a role in chronic inflammations and may stimulate production of constitutive rather than inflammatory chemokines and cytokines. Forms a receptor signaling complex with TYROBP and triggers activation of the immune responses in macrophages and dendritic cells.[1] Publication Abstract from PubMedSequence variants of the microglial expressed TREM2 (triggering receptor expressed on myeloid cells 2) are a major risk factor for late onset Alzheimer's disease. TREM2 requires a stable interaction with DAP12 in the membrane to initiate signaling, which is terminated by TREM2 ectodomain shedding and subsequent intramembrane cleavage by gamma-secretase. To understand the structural basis for the specificity of the intramembrane cleavage event, we determined the solution structure of the TREM2 transmembrane helix (TMH). Caused by the presence of a charged amino acid in the membrane region, the TREM2-TMH adopts a kinked structure with increased flexibility. Charge removal leads to TMH stabilization and reduced dynamics, similar to its structure in complex with DAP12. Strikingly, these dynamical features match with the site of the initial gamma-secretase cleavage event. These data suggest an unprecedented cleavage mechanism by gamma-secretase where flexible TMH regions act as key determinants of substrate cleavage specificity. gamma-Secretase cleavage of the Alzheimer risk factor TREM2 is determined by its intrinsic structural dynamics.,Steiner A, Schlepckow K, Brunner B, Steiner H, Haass C, Hagn F EMBO J. 2020 Aug 24:e104247. doi: 10.15252/embj.2019104247. PMID:32830336[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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Categories: Homo sapiens | Large Structures | Brunner B | Haass C | Hagn F | Schlepkow K | Steiner A | Steiner H