Notes 20101122 McConkey Group Meeting -- Owen Platypus
From SnOwy - Ed's Wiki Notebook
Owen's had a bit of a history of working with platypus venom proteins -- as I recall, this cocktail contains an exemplar from each of the protein superfolds and also most of the venom protein families found in the remainder of all animals -- convergent evolution etc.,
Structural Modelling -- Convergent Evolution
- transition from normal functions to venomous function is interesting
- venom evolution -- an interesting case of convergent evolution
- independent insertion events leading to venoms: shrews; Mexican bearded lizard;
- venomous shrews -- kallikrein-like peptide
- serine protease family
- also present in the platypus cDNA library
- there are seven good serine protease secretion candidates in the known platypus cocktail
- results of shrew paper -- major differences
- loop regions of protease are positively selected -- hydropathy and charge is increased
- pair of insertions in loop region -- loop one has two insertions; loop two and three each have one insertion
- the insertions increase the protease function of these proteins
- kallikreins employed in Mexican bearded lizard -- had strikingly similar insertions and mutations
- MODELER used to create a structure visualization
- Chimera has an interface with MODELER -- makes MODELER easier to use (until the interface stops working)
- SWISS-MODEL uses sequence-to-structure alignment -- aligns sequences onto homologous structures
Questions
- Why MUSCLE if it won't align well?
- Platypus self-immunity? comments?
