Identification of distal cis-regulatory elements at mouse mitoferrin loci using zebrafish transgenesis.

Authors

J D. Amigo
M Yu
M B. Troadec
B Gwynn
J D. Cooney
M J. Weiss
L L. PetersFollow
J Kaplan
A B. Cantor
B H. Paw

Document Type

Article

Publication Date

2011

Keywords

Base-Pairing, Base-Sequence, Binding-Sites, Chromatin-Immunoprecipitation, Enhancer-Elements-Genetic, Erythropoiesis, GATA1-Transcription-Factor, Gene-Expression-Regulation, Gene-Transfer-Techniques, Genes-Reporter, Genetic-Loci, Genome, Green-Fluorescent-Proteins, Heart, Membrane-Transport-Proteins, Mice, Molecular-Sequence-Data, Promoter-Regions-Genetic, Protein-Binding, Transcription-Factors, Transcription-Genetic, Zebrafish, Zebrafish-Proteins

JAX Source

Mol Cell Biol 2011 Apr; 31(7):1344-56.

First Page

1344

Last Page

1356

Abstract

Mitoferrin 1 (Mfrn1; Slc25a37) and mitoferrin 2 (Mfrn2; Slc25a28) function as essential mitochondrial iron importers for heme and Fe/S cluster biogenesis. A genetic deficiency of Mfrn1 results in a profound hypochromic anemia in vertebrate species. To map the cis-regulatory modules (CRMs) that control expression of the Mfrn genes, we utilized genome-wide chromatin immunoprecipitation (ChIP) datasets for the major erythroid transcription factor GATA-1. We identified the CRMs that faithfully drive the expression of Mfrn1 during blood and heart development and Mfrn2 ubiquitously. Through in vivo analyses of the Mfrn-CRMs in zebrafish and mouse, we demonstrate their functional and evolutionary conservation. Using knockdowns with morpholinos and cell sorting analysis in transgenic zebrafish embryos, we show that GATA-1 directly regulates the expression of Mfrn1. Mutagenesis of individual GATA-1 binding cis elements (GBE) demonstrated that at least two of the three GBE within this CRM are functionally required for GATA-mediated transcription of Mfrn1. Furthermore, ChIP assays demonstrate switching from GATA-2 to GATA-1 at these elements during erythroid maturation. Our results provide new insights into the genetic regulation of mitochondrial function and iron homeostasis and, more generally, illustrate the utility of genome-wide ChIP analysis combined with zebrafish transgenesis for identifying long-range transcriptional enhancers that regulate tissue development.

Recommended Citation

Amigo JD, Yu M, Troadec MB, Gwynn B, Cooney JD, Weiss MJ, Peters LL, Kaplan J, Cantor AB, Paw BH. Identification of distal cis-regulatory elements at mouse mitoferrin loci using zebrafish transgenesis. Mol Cell Biol 2011 Apr; 31(7):1344-56.