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Published on: August 15, 2017
Complete cDNA sequence of SAP-like pentraxin from Limulus polyphemus: implications for pentraxin evolution
Hazel A Tharia1, Annette K Shrive, John D Mills
1School of Life Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK.
Journal of Molecular Biology
|February 28, 2002
Summary
A new Limulus polyphemus SAP-like pentraxin was identified, distinct from other horseshoe crab pentraxins. Phylogenetic analysis suggests independent evolution of C-reactive protein and serum amyloid P component genes in arthropods and chordates.
Area of Science:
- Biochemistry
- Evolutionary Biology
- Molecular Biology
Background:
- Serum amyloid P component (SAP)-like pentraxin Limulus polyphemus SAP is a distinct species.
- It does not bind phosphocholine and has a unique N-terminal sequence compared to other horseshoe crab pentraxins.
Purpose of the Study:
- Determine the complete cDNA and amino acid sequence of Limulus SAP.
- Investigate the evolutionary relationship of Limulus SAP to other pentraxins.
Main Methods:
- cDNA sequencing
- Amino acid sequence analysis
- Phylogenetic analysis
Main Results:
- The complete cDNA and derived amino acid sequence of Limulus SAP were determined.
- Limulus SAP clusters with horseshoe crab C-reactive proteins (CRPs) in phylogenetic analysis.
- Limulus SAP shares 22% identity with human SAP and CRP, and 31-35% with horseshoe crab CRPs.
Conclusions:
- Gene duplication and divergence of CRP/SAP occurred independently in arthropod and chordate lineages.
- The CRP/SAP gene duplication in Limulus predates Limulus CRP variants and mammalian CRP/SAP duplication.
- Limulus SAP represents a distinct pentraxin species separate from other horseshoe crab pentraxins.
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