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Theme and variations: evolutionary diversification of the HET-s functional amyloid motif.

ABSTRACT: In mammals and fungi, Nod-like receptors (NLR) activate downstream cell death execution proteins by a prion-like mechanism. In Podospora anserina, the NWD2 NLR activates the HET-S Helo-domain pore-forming protein by converting its prion-forming domain into a characteristic ?-solenoid amyloid fold. The amyloid forming region of HET-S/s comprises two repetitions of a 21 amino acid motif. Herein, we systematically analyze the sequences of C-terminal regions of fungal HeLo and HeLo-like domain proteins to identify HET-s-related amyloid motifs (HRAM). We now identify four novel HRAM subfamilies in addition to the canonical HET-S/s subfamily. These novel motifs share the pseudo-repeat structure of HET-S/s and a specific pattern of distribution of hydrophobic and polar residues. Sequence co-variance analyses predict parallel in-register ?-stacking of the two repeats and residue-residue interactions compatible with the ?-solenoid fold. As described for HET-S, most genes encoding the HeLo proteins are adjacent to genes encoding NLRs also displaying HRAMs. The motifs of the NLRs are similar to those of their cognate HeLo-domain protein, indicating concerted evolution between repeats. This study shows that HET-s-related amyloid motifs are more common than anticipated and that they have diversified into discrete subfamilies that apparently share a common overall fold.

SUBMITTER: Daskalov A

PROVIDER: S-EPMC4518210 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Theme and variations: evolutionary diversification of the HET-s functional amyloid motif.

Daskalov Asen A Dyrka Witold W Saupe Sven J SJ

Scientific reports 20150729

In mammals and fungi, Nod-like receptors (NLR) activate downstream cell death execution proteins by a prion-like mechanism. In Podospora anserina, the NWD2 NLR activates the HET-S Helo-domain pore-forming protein by converting its prion-forming domain into a characteristic β-solenoid amyloid fold. The amyloid forming region of HET-S/s comprises two repetitions of a 21 amino acid motif. Herein, we systematically analyze the sequences of C-terminal regions of fungal HeLo and HeLo-like domain prote ...[more]

PMID: 26219477

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Theme and variations: evolutionary diversification of the HET-s functional amyloid motif.

Publications

Theme and variations: evolutionary diversification of the HET-s functional amyloid motif.

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