Identification and characterization of an R-Smad homologue (Hco-DAF-8) from Haemonchus contortus

摘要

Amino acid sequence alignment of DAF-8 with those of 10 R-Smads from selected species, including one nematode ( ), one arthropod ( ) and three chordates ( and ). Sequence motifs, such as MH1 (pink), MH2 (blue) and the phosphorylation motif (****) are marked. Within the MH1 region, the predicted nuclear localisation signal (NLS) is underlined. Within the linker region between the MH1 and the MH2 domain of -DAF-8, prolines (yellow) and SP motifs (open squares) which function as target sites for phosphorylation intracellular serine/threonine kinases are highlighted. Within the MH2 domain, black arrow indicates the conserved residues involved in TGF-β/Activin-activated R-Smads interaction with SARA; open circle indicates conserved residues of the nuclear export signal. The L3 loop sequence (18 amino acids) is shown (wavy line below the alignment) with R-Smad subtype-specific amino acid residues highlighted with red arrows at the top. The sequence percent identities (%) of -DAF-8 with the other R-Smads are listed at the end of the alignment. Information on sequences in the alignment is listed in Additional file : Table S2