Studies On The Preparation Of Histone H3-magnetic Beads And The Interactional Protein With Histones

Nucleuses of pig liver cells were extracted by freezing,fracturing and homogenate.Chromosome was obtained by cell disruption and dissociation,and was cut by ultrasonic wav.The core histones and histone H3 were precipitated and purified by salt concentration gradient.SDS-PAGE analysis showed that histones obtained were relatively pure.The extracted core histones were immobilized onto Sepharose-4B column,which was used to pull down histones-binding proteins from milk casein.The coupling rate is 1.12 mg/g.The proteins with molecular weight of 29.0kDa and 33.0kDa were obtained which were indicated to be PrP~c.These proteins were immobilized onto Sephrarose-4B column to prove the interaction between core-histones and PrP~c.SDS-PAGE showed histone H3 was wer obtained,which proved the interaction existed.The extracted histones H3 were immobilized onto magnetic beads with a carboxyl group,which was used to pull down histone H3-binding proteins from milk and rabbit plasma.The coupling rate is 117.05 ?g/mg The accordant result showed that two proteins with molecular weight of 29.0kDa and 33.0kDa were obtained from milk casein by the magnetic beads.The weak interactional proteins with histone H3 were eluted by PBST,while the strong interactional proteins that attached with histone H3 in stable were obtained.The effert of magnetic beads immobilized with histones was a contrast to Sepharose-4B immobilized with histones.A strong interactional protein with the molecular weight of 16 k Da was pulled down from milk supernatant.Some strong interactional proteins with histones were pulled down from rabbit plasma,including two proteins with molecular weight of 50 kDa and 66.4kDa.