GATA factors are essential for activity of the neuron-specific enhancer of the gonadotropin-releasing hormone gene

Mol Cell Biol. 1996 Jul;16(7):3596-605. doi: 10.1128/MCB.16.7.3596.

Abstract

The multicomponent neuron-specific enhancer of the gonadotropin-releasing hormone (GnRH) gene specifically targets expression to the GnRH-secreting neurons of the hypothalamus, a small population of specialized cells which play a central role in regulating reproductive function. Utilizing the GnRH-secreting hypothalamic neuronal cell line, GT1, as a model system, we show that members of the GATA family of transcription factors regulate GnRH transcription through two GATA factor-binding motifs that occur in a tandem repeat within the GnRH neuron-specific enhancer. Although GT1 cells contain GATA-2 and GATA-4 mRNAs, only GATA-4 was detected in a GnRH enhancer GATA site-specific complex. Cotransfection experiments with wild-type and mutant GnRH enhancer reporter plasmids with wild-type and dominant negative GATA factor expression vectors demonstrated that both GATA-binding elements are functional in the context of the enhancer. We conclude that GATA-binding proteins are important factors in regulating the neuron-specific expression of the GnRH gene in hypothalamic cells. Although the presence of GATA-2 in a neuronal cell type is not unusual, the presence of GATA-4 in GT1 cells is novel for a neuronal cell type. However, the presence of GATA-4 is consistent with the unique developmental origin of GnRH neurons and may provide insight into the transcriptional mechanisms mediating the differentiation of this limited population of GnRH-secreting neurons.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 3T3 Cells
  • Animals
  • Base Sequence
  • Binding Sites
  • Cell Line
  • Chloramphenicol O-Acetyltransferase / biosynthesis
  • DNA-Binding Proteins / metabolism*
  • Enhancer Elements, Genetic*
  • GATA2 Transcription Factor
  • GATA4 Transcription Factor
  • Gonadotropin-Releasing Hormone / biosynthesis*
  • Gonadotropin-Releasing Hormone / genetics*
  • Hypothalamus / metabolism*
  • Mice
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Neurons / metabolism*
  • Nuclear Proteins / metabolism
  • Oligonucleotide Probes
  • Recombinant Proteins / biosynthesis
  • Transcription Factors / metabolism*
  • Transcription, Genetic
  • Transfection
  • Zinc Fingers

Substances

  • DNA-Binding Proteins
  • GATA2 Transcription Factor
  • GATA4 Transcription Factor
  • Gata2 protein, mouse
  • Nuclear Proteins
  • Oligonucleotide Probes
  • Recombinant Proteins
  • Transcription Factors
  • Gonadotropin-Releasing Hormone
  • Chloramphenicol O-Acetyltransferase