Schistosoma mansoni encodes SMT3B and SMT3C molecules responsible for post-translational modification of cellular proteins.

Resumo
The sumoylation pathway is a post-translational modification of nuclear proteins widespread among several organisms. SMT3C is the main protein involved in this process and it is covalently conjugated to a diverse assortment of nuclear protein targets. To date, 3 SUMO paralogues (SMT3C, A/B) have been characterized in mammals and plants. In this work we characterized two SUMO related genes, named SMT3B and SMT3C throughout Schistosoma mansoni life cycle. The SmSMTB/C encodes for proteins sharing significant amino acid homology with SMT3. Phylogenetical analyses revealed that both SmSMT3B/C are distinct proteins. Additionally, SmSMT3B and C are expressed in cercariae, adult worms, eggs and schistosomula however SmSMT3C gene showed an expression level 7 to 9 fold higher than SmSMT3B in eggs, schistosomula and adult worms. The comparison between the SmSMT3C genomic and cDNA sequences established that the encoding sequence is interrupted by 3 introns of 70, 37 and 36 bp. Western Blot has shown SMT3 conjugates are present in nuclear and total protein fractions of adults and cercariae. Therefore our results suggest a functional sumoylation pathway, and the presence of two paralogues also suggests the specificity of substrates for SMT3 in S. mansoni.
Descrição
Palavras-chave
Schistosoma mansoni, Post-translational modification, Sumoylation
Citação
CABRAL, F. J. et al. Schistosoma mansoni encodes SMT3B and SMT3C molecules responsible for post-translational modification of cellular proteins. Parasitology International, v. 57, p. 172-178, 2008. Disponível em: <https://www.sciencedirect.com/science/article/pii/S1383576907001596>. Acesso em: 08 nov. 2014.