Effect Of Sodium Salt On Aggregation States Of Chicken Cystatin Amyloidogenic Mutant I66Q

The soluble-insoluble state of Human Cystatin C?HCC?in body fluids are closely related with multiple cerebral vascular disease and Alzheimer's disease.The reason is the L68Q mutants is the causative agent of HCCAA.The study of the influence of different kinds of sodium salt on HCC aggregation characteristics can provide necessary information and clues on elucidation of the HCC amyloidogenic properties as well as the locations of its aggegation in body fluids.As cC has highly homology with HCC and the I66Q mutants of cC is correspond with the L68Q mutants,It has already been verified that it is more feasible,economical and convenient to study the amyloidogenic properties as well as its biological activities by using cC instead of HCC.In this study,with 0.1M of NaCl?NaBr?NaF?Nal?NaH₂PO₄?NaNO₃?CH₃COONa added in yeast liquid medium,using the techniques of SDS-PAGE,we found that the chicken cystatin I66Q was mainly gathered at oligomeric states increased.with 0.1M NaH₂PO₄,but others salt has no effecting.In this study,with different kinds of sodium salt added in yeast liquid medium,using the techniques of SDS-PAGE and western blot,combined with molecular dynamics,we found that the chicken cystatin I66Q was mainly gathered at soluble oligomeric states as the NaH₂PO₄ concentration increased.Thus,we proposed that the NaH₂PO₄ has a role in preventing amyloid firbril formation by accumulating the soluble oligomers of HCC at a certain level,although this effect would greatly result in the decrease of its inhibitory activity.This study can be very helpful to illustrate the mechanism of effections of ions on cystatin structural stability.