High mobility group non-histone chromosomal proteins from chicken thrombocytes and erythrocytes.

The high mobility group non-histone chromosomal proteins (HMG) from chicken thrombocytes were compared with those from chicken erythrocytes. In terms of their extractability, electrophoretic behaviour in polyacrylamide gels containing 2.5 M-urea, and amino acid composition, the HMG proteins of these cells were indistinguishable. However, microcomplement fixation assay performed in the presence of antiserum against HMG-1 and HMG-2 revealed that these high molecular weight HMG proteins of chicken thrombocytes and erythrocytes are not cross-reactive. Electrophoretic analysis of HMG-1 and HMG-2 from these two types of cells in polyacrylamide gels containing 6.25 M-urea suggested differences in the HMG-2 patterns.