ZNF410 uniquely activates the NuRD component CHD4 to silence fetal hemoglobin expression

Abstract

Metazoan transcription factors typically regulate large numbers of genes. Here we identify via a CRISPR-Cas9 genetic screen ZNF410, a pentadactyl DNA binding protein that in human erythroid cells directly and measurably activates only one gene, the NuRD component CHD4. Specificity is conveyed by two highly evolutionarily conserved clusters of ZNF410 binding sites near the CHD4 gene with no counterparts elsewhere in the genome. Loss of ZNF410 in adult-type human erythroid cell culture systems and xenotransplant settings diminishes CHD4 levels and derepresses the fetal hemoglobin genes. While previously known to be silenced by CHD4, the fetal globin genes are exposed here as among the most sensitive to reduced CHD4 levels. In vitro DNA binding assays and crystallographic studies reveal the ZNF410-DNA binding mode. ZNF410 is a remarkably selective transcriptional activator in erythroid cells whose perturbation might offer new therapeutic opportunities in the treatment of hemoglobinopathies. HighlightsO_LIA CRISPR screen implicates ZNF410 in fetal globin gene repression C_LIO_LIThe CHD4 gene is the singular direct ZNF410 target in erythroid cells C_LIO_LIThe fetal globin genes are exquisitely sensitive to CHD4 levels C_LIO_LIFive C2H2 zinc fingers of ZNF410 recognize the major groove of a 14 base pair sequence C_LI