Method for monitoring post-translational modification of protein

Abstract

According to a method for monitoring post-translational modifications of protein is provided, a first microbead by binding a protein antibody to a base bead is provided. A second microbead by binding a target protein having a first post-translational modification or a second post-translational modification, which are inversely proportional to each other, to the protein antibody of the first microbead, is provided. A third microbead by binding the second microbead to a first post-translational modification antibody is provided. A fourth microbead by binding the second microbead to a second post-translational modification antibody is provided. Impedances of the third and fourth microbeads are measured. A ratio of a first difference, between the impedances of the third microbead and a reference impedance, to a second difference, between the impedances of the fourth microbead and the reference impedance, is obtained.

1 . A method for monitoring post-translational modifications of protein, the method comprising:
 combining a first post-translational modification of target proteins with a first post-translational modification antibody capable of being selectively combined with the first post-translational modification to prepare a first post-translational modification medium;   combining a second post-translational modification of target proteins with a second post-translational modification antibody capable of being selectively combined with the second post-translational modification to prepare a second post-translational modification medium, the second post-translational modification being inversely proportional to the first post-translational modification;   obtaining a first measured value of the first post-translational modification medium for a physical characteristic or a chemical characteristic, which varies depending on degree of the first post-translational modification and the second post-translational modification;   obtaining a second measured value of the second post-translational modification medium for the physical characteristic or the chemical characteristic; and   obtaining a ratio of a first difference to a second difference, wherein the first difference is a difference between the first measured value and a reference value, and the second difference is a difference between the second measured value and the reference value.   
     
     
         2 . The method of  claim 1 , wherein the target proteins are au proteins. 
     
     
         3 . The method of  claim 2 , wherein the first post-translational modification is phosphorylated tau protein, and the second post-translational modification is O-glycosylated tau protein. 
     
     
         4 . The method of  claim 1 , wherein each of the first measured value and the second measured value is an impedance. 
     
     
         5 . The method of  claim 1 , wherein each of the first post-translational modification medium and the second post-translational modification medium includes a fluorescence or a chemiluminescence, and
 wherein each of the first measured value and the second measured value is a measured value of an optical characteristic varying depending on an amount of the fluorescence or the chemiluminescence.   
     
     
         6 . The method of  claim 1 , wherein the first post-translational modification medium includes a base bead combined with the target proteins and the first post-translational modification antibody, and wherein the second post-translational modification medium includes a base bead combined with the target proteins and the second post-translational modification antibody. 
     
     
         7 . The method of  claim 6 , wherein obtaining the first measured value include disposing the first post-translational modification medium between a first electrode and a second electrode to obtain an impedance of the first post-translational modification medium. 
     
     
         8 . The method of  claim 6 , wherein the base bead include a magnetic bead. 
     
     
         9 . The method of  claim 8 , wherein the first post-translational modification medium including the magnetic bead is moved between the first and second electrodes by a magnetic substance. 
     
     
         10 . The method of  claim 6 , wherein the reference value is an impedance of a base bead combined with the target proteins without either the first post-translational modification antibody or the second post-translational modification antibody.