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Processing of Plasmodium falciparum Merozoite Surface Protein MSP1 Activates a Spectrin-Binding Function Enabling Parasite Egress from RBCs.

Das S, Hertrich N, Perrin AJ, Withers-Martinez C, Collins CR, Jones ML, Watermeyer JM, Fobes ET, Martin SR, Saibil HR, Wright GJ, Treeck M, Epp C, Blackman MJ - Cell Host Microbe (2015)

Bottom Line: The function of MSP1 and its processing are unknown.Here we show that SUB1-mediated processing of MSP1 is important for parasite viability.Parasites expressing an inefficiently processed MSP1 mutant show delayed egress, and merozoites lacking surface-bound MSP1 display a severe egress defect.

View Article: PubMed Central - PubMed

Affiliation: The Francis Crick Institute, Mill Hill Laboratory, Mill Hill, London, NW7 1AA, UK.

No MeSH data available.


Related in: MedlinePlus

Alternative 38/42 Processing Sites in MSP1(A) P. falciparum MSP1 and primary processing products. Known and predicted PfSUB1 cleavage sites in MSP1-D and MSP1-F (colored horizontal bars), above an alignment of flanking sequences, with experimentally confirmed cleavage sites arrowed and indicated by gaps. The 38/42 region contains the canonical cleavage site (can) as well as two additional sites (alt1 and alt2) confirmed in this work. MSP1-F contains a further predicted 38/42 site (HVGAE↓SNTIT; green bar) but this study found no evidence for cleavage at that site.(B) Cleavage by rPfSUB1 of peptides based on alternative 38/42 processing sites. RP-HPLC elution profiles of N-acetylated decapeptides before or after incubation with rPfSUB1. Parental peptide peaks diminished over time, with concomitant increase in the indicated products. In the case of Ac-PIFGESEDND the C-terminal cleavage product was too hydrophilic to bind to the RP-HPLC column. The small peak near the end of each chromatogram that does not alter with time represents elution of detergent from the digestion buffer.(C) The 38/42alt1 peptides are better substrates than the canonical 38/42 site peptides. Equimolar mixtures of peptides based on the canonical 38/42 and 38/42alt1 sites in MSP1-F and MSP1-D were incubated with rPfSUB1 and the peak area for substrate and product(s) monitored with time. Initial cleavage rates were compared after no more than 10% of the fastest cleaved peptide had been hydrolyzed, though for clarity extended digestions are also shown. Cleavage of both 38/42alt1 peptides occurred at least 6.7 times faster than cleavage of the corresponding canonical 38/42 site peptide. See also Figure S1.
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fig1: Alternative 38/42 Processing Sites in MSP1(A) P. falciparum MSP1 and primary processing products. Known and predicted PfSUB1 cleavage sites in MSP1-D and MSP1-F (colored horizontal bars), above an alignment of flanking sequences, with experimentally confirmed cleavage sites arrowed and indicated by gaps. The 38/42 region contains the canonical cleavage site (can) as well as two additional sites (alt1 and alt2) confirmed in this work. MSP1-F contains a further predicted 38/42 site (HVGAE↓SNTIT; green bar) but this study found no evidence for cleavage at that site.(B) Cleavage by rPfSUB1 of peptides based on alternative 38/42 processing sites. RP-HPLC elution profiles of N-acetylated decapeptides before or after incubation with rPfSUB1. Parental peptide peaks diminished over time, with concomitant increase in the indicated products. In the case of Ac-PIFGESEDND the C-terminal cleavage product was too hydrophilic to bind to the RP-HPLC column. The small peak near the end of each chromatogram that does not alter with time represents elution of detergent from the digestion buffer.(C) The 38/42alt1 peptides are better substrates than the canonical 38/42 site peptides. Equimolar mixtures of peptides based on the canonical 38/42 and 38/42alt1 sites in MSP1-F and MSP1-D were incubated with rPfSUB1 and the peak area for substrate and product(s) monitored with time. Initial cleavage rates were compared after no more than 10% of the fastest cleaved peptide had been hydrolyzed, though for clarity extended digestions are also shown. Cleavage of both 38/42alt1 peptides occurred at least 6.7 times faster than cleavage of the corresponding canonical 38/42 site peptide. See also Figure S1.

Mentions: P. falciparum MSP1 is a polymorphic protein that exists in two major isoforms, typified by those of the 3D7 and FCB1 parasite isolates. N-terminal sequencing has mapped three positionally conserved primary processing sites in each of these MSP1 isoforms (Blackman et al., 1991; Cooper and Bujard, 1992; Heidrich et al., 1989; Koussis et al., 2009; Stafford et al., 1994). The sites are referred to as 83/30, 30/38, and 38/42, after the approximate masses of the cleavage products (Figure 1A). While all are cleaved by P. falciparum SUB1 (PfSUB1), they are structurally distinct, consistent with evidence that PfSUB1 accommodates flexibility in its recognition motif (Withers-Martinez et al., 2012). Only the 38/42 site (i.e., that closest to the C terminus of MSP1) shows significant similarity between 3D7 MSP1 (MSP1-D) and FCB1 MSP1 (MSP1-F) (Figure 1A). Cleavage at the 38/42 site is a rate-limiting processing step (Child et al., 2010), implying special importance.


Processing of Plasmodium falciparum Merozoite Surface Protein MSP1 Activates a Spectrin-Binding Function Enabling Parasite Egress from RBCs.

Das S, Hertrich N, Perrin AJ, Withers-Martinez C, Collins CR, Jones ML, Watermeyer JM, Fobes ET, Martin SR, Saibil HR, Wright GJ, Treeck M, Epp C, Blackman MJ - Cell Host Microbe (2015)

Alternative 38/42 Processing Sites in MSP1(A) P. falciparum MSP1 and primary processing products. Known and predicted PfSUB1 cleavage sites in MSP1-D and MSP1-F (colored horizontal bars), above an alignment of flanking sequences, with experimentally confirmed cleavage sites arrowed and indicated by gaps. The 38/42 region contains the canonical cleavage site (can) as well as two additional sites (alt1 and alt2) confirmed in this work. MSP1-F contains a further predicted 38/42 site (HVGAE↓SNTIT; green bar) but this study found no evidence for cleavage at that site.(B) Cleavage by rPfSUB1 of peptides based on alternative 38/42 processing sites. RP-HPLC elution profiles of N-acetylated decapeptides before or after incubation with rPfSUB1. Parental peptide peaks diminished over time, with concomitant increase in the indicated products. In the case of Ac-PIFGESEDND the C-terminal cleavage product was too hydrophilic to bind to the RP-HPLC column. The small peak near the end of each chromatogram that does not alter with time represents elution of detergent from the digestion buffer.(C) The 38/42alt1 peptides are better substrates than the canonical 38/42 site peptides. Equimolar mixtures of peptides based on the canonical 38/42 and 38/42alt1 sites in MSP1-F and MSP1-D were incubated with rPfSUB1 and the peak area for substrate and product(s) monitored with time. Initial cleavage rates were compared after no more than 10% of the fastest cleaved peptide had been hydrolyzed, though for clarity extended digestions are also shown. Cleavage of both 38/42alt1 peptides occurred at least 6.7 times faster than cleavage of the corresponding canonical 38/42 site peptide. See also Figure S1.
© Copyright Policy - CC BY
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4608996&req=5

fig1: Alternative 38/42 Processing Sites in MSP1(A) P. falciparum MSP1 and primary processing products. Known and predicted PfSUB1 cleavage sites in MSP1-D and MSP1-F (colored horizontal bars), above an alignment of flanking sequences, with experimentally confirmed cleavage sites arrowed and indicated by gaps. The 38/42 region contains the canonical cleavage site (can) as well as two additional sites (alt1 and alt2) confirmed in this work. MSP1-F contains a further predicted 38/42 site (HVGAE↓SNTIT; green bar) but this study found no evidence for cleavage at that site.(B) Cleavage by rPfSUB1 of peptides based on alternative 38/42 processing sites. RP-HPLC elution profiles of N-acetylated decapeptides before or after incubation with rPfSUB1. Parental peptide peaks diminished over time, with concomitant increase in the indicated products. In the case of Ac-PIFGESEDND the C-terminal cleavage product was too hydrophilic to bind to the RP-HPLC column. The small peak near the end of each chromatogram that does not alter with time represents elution of detergent from the digestion buffer.(C) The 38/42alt1 peptides are better substrates than the canonical 38/42 site peptides. Equimolar mixtures of peptides based on the canonical 38/42 and 38/42alt1 sites in MSP1-F and MSP1-D were incubated with rPfSUB1 and the peak area for substrate and product(s) monitored with time. Initial cleavage rates were compared after no more than 10% of the fastest cleaved peptide had been hydrolyzed, though for clarity extended digestions are also shown. Cleavage of both 38/42alt1 peptides occurred at least 6.7 times faster than cleavage of the corresponding canonical 38/42 site peptide. See also Figure S1.
Mentions: P. falciparum MSP1 is a polymorphic protein that exists in two major isoforms, typified by those of the 3D7 and FCB1 parasite isolates. N-terminal sequencing has mapped three positionally conserved primary processing sites in each of these MSP1 isoforms (Blackman et al., 1991; Cooper and Bujard, 1992; Heidrich et al., 1989; Koussis et al., 2009; Stafford et al., 1994). The sites are referred to as 83/30, 30/38, and 38/42, after the approximate masses of the cleavage products (Figure 1A). While all are cleaved by P. falciparum SUB1 (PfSUB1), they are structurally distinct, consistent with evidence that PfSUB1 accommodates flexibility in its recognition motif (Withers-Martinez et al., 2012). Only the 38/42 site (i.e., that closest to the C terminus of MSP1) shows significant similarity between 3D7 MSP1 (MSP1-D) and FCB1 MSP1 (MSP1-F) (Figure 1A). Cleavage at the 38/42 site is a rate-limiting processing step (Child et al., 2010), implying special importance.

Bottom Line: The function of MSP1 and its processing are unknown.Here we show that SUB1-mediated processing of MSP1 is important for parasite viability.Parasites expressing an inefficiently processed MSP1 mutant show delayed egress, and merozoites lacking surface-bound MSP1 display a severe egress defect.

View Article: PubMed Central - PubMed

Affiliation: The Francis Crick Institute, Mill Hill Laboratory, Mill Hill, London, NW7 1AA, UK.

No MeSH data available.


Related in: MedlinePlus