Structural elucidation of the protein- and membrane-binding properties of the N-terminal tail domain of human annexin II.
The conformational preferences and the solution structure of AnxII(N31), a peptide corresponding to the full-length sequence (residues 1-31) of the human annexin II N-terminal tail domain, were investigated by circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy. CD results showed that AnxII(N31) adopts a mainly alpha-helical conformation in hydrophobic or membrane-mimetic environments, while a predominantly random structure is adopted in aqueous buffer. In contrast to previous results of the annexin I N-terminal domain peptide [Yoon et al. (2000) FEBS Lett. 484, 241-245], calcium ions showed no effect on the structure of AnxII(N31). The NMR-derived structure of AnxII(N31) in 50% TFE/water mixture showed a horseshoe-like fold comprising the N-terminal amphipathic alpha-helix, the following loop, and the C-terminal helical region. Together, the results establish the first detailed structural data on the N-terminal tail domain of annexin II, and suggest the possibility of the domain to undergo Ca(2+)-independent membrane-binding.
Hong
Yoon-Hun
YH
National Research Laboratory (MPS), College of Pharmacy, Seoul National University, San 56-1, Shillim-Dong, Kwanak-Gu, Seoul 151-742, Korea.
Won
Hyung-Sik
HS
Ahn
Hee-Chul
HC
Lee
Bong-Jin
BJ
D017306:Annexin A2 / Q000737:chemistry* / Q000378:metabolism; D002021:Buffers; D002942:Circular Dichroism / Q000379:methods; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary / Q000502:physiology; D012997:Solvents / Q000378:metabolism
D017306:Annexin A2; D002021:Buffers; D012997:Solvents