Gene expression in response to depletion of specific human histone H1 isoforms.

At least six histone H1 variants exist in mammalian somatic cells that bind to the linker DNA and stabilize the nucleosome particle contributing to higher order chromatin compaction. In addition, H1 seems to be involved in the active regulation of gene expression. It is not well known whether the different variants have specific roles or regulate specific promoters. We have explored this by inducible shRNA-mediated knock-down of each of the H1 variants in a human breast cancer cell line. A different subset of genes is altered in each H1 knock-down. Keywords: cell type comparison; genetic modification; RNA interference Stable breast cancer-derived cell lines expressing an shRNA against one of each of the histone H1 isoforms in response to doxycycline (Dox) were grown for six days in the presence or absence of Dox, in duplicate, and RNA extracted for microarray hybridization. Cell lines used: inducible shRNA against H1.0, H1.2, H1.3, H1.4, H1.5, and control/empty shRNA-expression vector.