A novel TMPRSS3 missense mutation in a DFNB8/10 family prevents proteolytic activation of the protein

Pathogenic mutations in TMPRSS3, which encodes a transmembrane serine protease, cause non-syndromic deafness DFNB8/10. Missense mutations map in the low density-lipoprotein receptor A (LDLRA), scavenger-receptor cysteine-rich (SRCR), and protease domains of the protein, indicating that all domains are important for its function. TMPRSS3 undergoes proteolytic cleavage and activates the ENaC sodium channel in a Xenopus oocyte model system. To assess the importance of this gene in non-syndromic childhood or congenital deafness in Turkey, we screened for mutations affected members of 25 unrelated Turkish families. The three families with the highest LOD score for linkage to chromosome 21q22.3 were shown to harbor P404L, R216L, or Q398X mutations, suggesting that mutations in TMPRSS3 are a considerable contributor to non-syndromic deafness in the Turkish population. The mutant TMPRSS3 harboring the novel R216L missense mutation within the predicted cleavage site of the protein fails to undergo proteolytic cleavage and is unable to activate ENaC, thus providing evidence that pre-cleavage of TMPRSS3 is mandatory for normal functio

A Case-Control Association Study of RANTES (-28C>G) Polymorphism as a Risk Factor for Parkinson’s Disease in Isparta, Turkey

Background. Recent studies have revealed that inflammatory processes are involved in the pathogenesis of Parkinson’s disease (PD). Multiple lines of evidence have suggested that chemokines and their receptors are involved in several neurodegenerative disorders. We have examined whether genetic polymorphisms at the genes encoding chemokines IL-8 (-251A>T), MCP-1 (-2518A/G), and RANTES (-28C>G) and chemokine receptors CCR2 (V64I) and CCR5 (-Δ32) were associated with sporadic PD risk in Isparta, Turkey. Method. The pilot case-control association study included 30 PD patients and 60 control subjects, who were all genotyped with PCR-RFLP for the five polymorphisms. Their genotype and haplotype frequencies were compared statistically. Results. One SNP (-28C>G) in RANTES revealed a significant association with PD (P (allele) < 0.0001, p-trend = 0.0007). The risk allele (G) in the homozygous and dominant models (OR = 17.29 and 32.10, 95% CI = 0.86–347.24 and 1.74–591.937, resp.) suggests additional PD risk. The haplotype TGCAN from the IL-8 (-251A>T), MCP-1 (-2518A>G), RANTES (-28C>G), CCR-2 (V64I), and CCR-5 (-Δ32) has protective effect (OR = 0.08 [CI = 0.01–0.63], p=0.019). Conclusions. Our data are the first indication of the role of RANTES (-28C>G) in PD risk

A novel TMPRSS3 missense mutation in a DFNB8/10 family prevents proteolytic activation of the protein.

Item does not contain fulltextPathogenic mutations in TMPRSS3, which encodes a transmembrane serine protease, cause non-syndromic deafness DFNB8/10. Missense mutations map in the low density-lipoprotein receptor A (LDLRA), scavenger-receptor cysteine-rich (SRCR), and protease domains of the protein, indicating that all domains are important for its function. TMPRSS3 undergoes proteolytic cleavage and activates the ENaC sodium channel in a Xenopus oocyte model system. To assess the importance of this gene in non-syndromic childhood or congenital deafness in Turkey, we screened for mutations affected members of 25 unrelated Turkish families. The three families with the highest LOD score for linkage to chromosome 21q22.3 were shown to harbor P404L, R216L, or Q398X mutations, suggesting that mutations in TMPRSS3 are a considerable contributor to non-syndromic deafness in the Turkish population. The mutant TMPRSS3 harboring the novel R216L missense mutation within the predicted cleavage site of the protein fails to undergo proteolytic cleavage and is unable to activate ENaC, thus providing evidence that pre-cleavage of TMPRSS3 is mandatory for normal function