Viral M45 and necroptosis‐associated proteins form heteromeric amyloid assemblies. (29th November 2018)

• Record Type: Journal Article
• Authors: Pham, Chi LL; Shanmugam, Nirukshan; Strange, Merryn; O'Carroll, Ailis; Brown, James WP; Sierecki, Emma; Gambin, Yann; Steain, Megan; Sunde, Margaret
• Is Part Of: EMBO reports. Volume 20:Number 2(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-11-29
• Subjects: amyloid -- M45 -- necroptosis -- RIP homotypic interaction motif -- RIPK3; Molecular biology -- Periodicals; Molecular Biology -- Periodicals; Molecular biology; Periodicals; 572.8
• DOI: 10.15252/embr.201846518
• Languages: English
• ISSNs: 1469-221X

Abstract

Abstract: The murine cytomegalovirus protein M45 protects infected mouse cells from necroptotic death and, when heterologously expressed, can protect human cells from necroptosis induced by tumour necrosis factor receptor (TNFR) activation. Here, we show that the N‐terminal 90 residues of the M45 protein, which contain a RIP homotypic interaction motif (RHIM), are sufficient to confer protection against TNFR‐induced necroptosis. This N‐terminal region of M45 drives rapid self‐assembly into homo‐oligomeric amyloid fibrils and interacts with the RHIMs of the human kinases RIPK1 and RIPK3, and the Z‐DNA binding protein 1 (ZBP1), to form heteromeric amyloid fibrils in vitro . Mutation of the tetrad residues in the M45 RHIM attenuates homo‐ and hetero‐amyloid assembly by M45, suggesting that the amyloidogenic nature of the M45 RHIM underlies its biological activity. The M45 RHIM preferentially interacts with RIPK3 and ZBP1 over RIPK1 and alters the properties of the host RHIM protein assemblies. Our results indicate that M45 mimics the interactions made by RIPK1 or ZBP1 with RIPK3, thereby forming heteromeric amyloid structures, which may explain its ability to inhibit necroptosis. Synopsis: The murine cytomegalovirus protein M45 forms heteromeric amyloid fibrils with RIPK1, ZBP1 and RIPK3 through its RIP homotypic interaction motif. The sequestration of RHIM proteins in M45‐contaning fibrils might explain its ability to inhibit necroptosis. The viral M45 protein forms functional amyloid fibrils. M45 forms heteromeric amyloid fibrils with host RHIM proteins. M45 preferentially interacts with ZBP1 and RIPK3 over RIPK1. Abstract : The murine cytomegalovirus protein M45 forms heteromeric amyloid fibrils with RIPK1, ZBP1 and RIPK3 through its RIP homotypic interaction motif. The sequestration of RHIM proteins in M45‐contaning fibrils might explain its ability to inhibit necroptosis.