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Biology subjects

Cornwall, G. A.

Publications and source records attributed to Cornwall, G. A..

2 recordsLinked to original sources

The Mouse Epididymal Amyloid Matrix: A Mammalian Counterpart of a Bacterial Biofilm

The mouse epididymis is a long tubule connecting the testis to the vas deferens. Its primary functions are to mature spermatozoa into motile and fertile cells and to protect them from pathogens that ascend the male tract. We previously demonstrated that a functional extracellular amyloid matrix surrounds spermatozoa in the epididymal lumen and has host defense functions; properties not unlike that of an extracellular biofilm that surrounds and protects a bacterial community. Here we show the epididymal amyloid matrix also structurally resembles a biofilm by containing eDNA, eRNA, and mucin-like polysaccharides. Further these structural components exhibit comparable behaviors and perform functions like their counterparts in bacterial biofilms. Our studies suggest that nature has used the ancient building blocks of bacterial biofilms to form an analogous structure that nurtures and protects the mammalian male germline.

cell biology↗

Pathogenic Mutations in the C2A Domain of Dysferlin form Amyloid that Activates the Inflammasome.

Limb-Girdle Muscular Dystrophy Type-2B/2R is caused by mutations in the dysferlin gene (DYSF). This disease has two known pathogenic missense mutations that occur within dysferlins C2A domain, namely C2AW52R and C2AV67D. Yet, the etiological rationale to explain the disease linkage for these two mutations is still unclear. In this study, we have presented evidence from biophysical, computational, and immunological experiments which suggest that these missense mutations interfere with dysferlins ability to repair cells. The failure of C2AW52R and C2AV67D to initiate membrane repair arises from their propensity to form stable amyloid. The misfolding of the C2A domain caused by either mutation exposes {beta}-strands, which are predicted to nucleate classical amyloid structures. When dysferlin C2A amyloid is formed, it triggers the NLRP3 inflammasome, leading to the secretion of inflammatory cytokines, including IL-1{beta}. The present study suggests that the muscle dysfunction and inflammation evident in Limb-Girdle Muscular Dystrophy types-2B/2R, specifically in cases involving C2AW52R and C2AV67D, as well as other C2 domain mutations with considerable hydrophobic core involvement, may be attributed to this mechanism.

biophysics↗