DEVELOPMENTAL-CHANGES IN TRANSCRIPTION FACTORS ASSOCIATED WITH THE NUCLEAR MATRIX OF CHICKEN ERYTHROCYTES

The nuclear matrix has roles in organizing nuclear DNA and in controll ing transcription. Transcription factors are associated with the nucle ar matrix, with the spectra of transcription factors differing from on e cell type to another. In this study we identified the transcription factors and enzymes functioning in the regulation of gene expression t hat were associated with nuclear matrix and nonmatrix nuclear fraction s in erythrocytes isolated from chick embryos at different stages or d evelopment, anemic and normal adult birds. We found that the primitive erythroid nuclear matrix had the greatest histone deacetylase activit y and highest levels of several transcription factors, including GATA- 1, CACCC-binding proteins, and NF1. These transcription Factors have k ey roles in erythroid-specific gene expression. The levels of these tr anscription factors were lower in the nonmatrix and matrix fractions i solated from definitive erythrocytes. For primitive and definitive ery throcytes, the level of CACCC-binding proteins in the nuclear matrix f raction was greater than that of Sp1. The relative levels of these tra nscription factors were,ere reversed in the nonmatrix fraction. Casein kinase II was not found in erythroid nuclear matrices. The observed e rythroid lineage specific alterations in erythroid nuclear matrix tran scription factor composition and abundance may be involved in erythroi d specific gene expression. (C) 1996 Wiley-Liss, Inc.