Peptidoglycan-Sensing Receptors Trigger the Formation of Functional Amyloids of the Adaptor Protein Imd to Initiate Drosophila NF-κB Signaling.

Published

Journal Article

In the Drosophila immune response, bacterial derived diaminopimelic acid-type peptidoglycan binds the receptors PGRP-LC and PGRP-LE, which through interaction with the adaptor protein Imd leads to activation of the NF-κB homolog Relish and robust antimicrobial peptide gene expression. PGRP-LC, PGRP-LE, and Imd each contain a motif with some resemblance to the RIP Homotypic Interaction Motif (RHIM), a domain found in mammalian RIPK proteins forming functional amyloids during necroptosis. Here we found that despite sequence divergence, these Drosophila cryptic RHIMs formed amyloid fibrils in vitro and in cells. Amyloid formation was required for signaling downstream of Imd, and in contrast to the mammalian RHIMs, was not associated with cell death. Furthermore, amyloid formation constituted a regulatable step and could be inhibited by Pirk, an endogenous feedback regulator of this pathway. Thus, diverse sequence motifs are capable of forming amyloidal signaling platforms, and the formation of these platforms may present a regulatory point in multiple biological processes.

Full Text

Duke Authors

Cited Authors

  • Kleino, A; Ramia, NF; Bozkurt, G; Shen, Y; Nailwal, H; Huang, J; Napetschnig, J; Gangloff, M; Chan, FK-M; Wu, H; Li, J; Silverman, N

Published Date

  • October 2017

Published In

Volume / Issue

  • 47 / 4

Start / End Page

  • 635 - 647.e6

PubMed ID

  • 29045898

Pubmed Central ID

  • 29045898

Electronic International Standard Serial Number (EISSN)

  • 1097-4180

International Standard Serial Number (ISSN)

  • 1074-7613

Digital Object Identifier (DOI)

  • 10.1016/j.immuni.2017.09.011

Language

  • eng