Separation and characterization of Arabidopsis thaliana proteins by two‐dimensional gel electrophoresis

Abstract

Arabidopsis (Arabidopsis thaliana) proteins were isolated from five tissues (leaf, stem, root, seed and callus), and separated by two‐dimensional gel electrophoresis (2‐DE). 2‐DE was carried out by immobilized pH gradient (IPG) in the first dimension, and by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) in the second dimension. With the aid of comigrated five‐marker proteins, the patterns of 2‐DE gels for each tissue were graphically combined by a computer into a single synthetic image for the integrated Arabidopsis protein spots. The protein spot images, altogether 4763, were characterized by both molecular mass and isoelectric point. Partial amino(N)‐terminal sequences of 101 protein spots were analyzed by Edman degradation. Fifty seven proteins were partially sequenced and 46 proteins appeared to have blocked N‐termini. Deblocking by hydrazine vapor was carried out on 14 proteins and two of them were found to be pyroglutamyl‐blocked N‐termini. Forty seven new proteins were found by the present investigation.