Two-dimensional gel analysis of proteins from human trisomy 21 fetal liver tissue after DEAE-Sepharose chromatography

Human liver protein map: a reference database established by microsequencing and gel comparison

This publication establishes a reference human liver protein map obtained with immobilized pH gradients. By microsequencing, 57 spots or 42 polypeptide chains were identified. By protein map comparison and matching (liver, red blood cell and plasma sample maps), 8 additional proteins were identified. The new polypeptides and previously known proteins are listed in a table and/or labeled on the protein map, thus providing a human liver two-dimensional gel database. This reference map can be used to identify protein spots on other samples such as rectal cancer biopsies.

Electrophoresis of mutant proteins in inherited diseases

The electrophoretic approaches for detection of mutant proteins in inherited diseases are briefly reviewed and discussed. Mutation of a protein, known to be associated with a specific inherited disease, is detected by immunoblotting, immunoprecipitation or enzyme staining, combined with various electrophoretic techniques. Some instrumental and technological devices for two-dimensional electrophoresis have been reported for the screening of mutant proteins in diseases of currently unknown etiology.

Analysis of protein patterns from different organs and cell fractions of trisomy 19 mice

Proteins were extracted from liver, brain, and skin of 6-day-old mice with trisomy (Ts) 19 and fractionated into solubilized cell proteins and structure-bound cell proteins. The proteins were separated by two-dimensional electrophoresis, and protein patterns were compared in the combinations Ts/normal and normal/normal. Analysis of the protein patterns revealed protein spots (variants) with densities higher (h-type) or lower (l-type) in trisomies than in normal mice. Some of these variants were found in all Ts individuals investigated for a particular protein class. These variants, termed regular Ts-variants, constituted 0.8%-1.6% of the total number of spots. The proteins of the regular Ts variants were in most cases organ-nonspecific. However, in almost all cases a given quantitative variation was expressed in only one of the three organs investigated. To explain our results, we have presented models for the control of protein levels on the basis of gene regulation. New aspects in the conception of studies on trisomies in man could be gained.