Heme utilization in the Caenorhabditis elegans hypodermal cells is facilitated by heme-responsive gene-2.

ABSTRACT: The roundworm Caenorhabditis elegans is a heme auxotroph that requires the coordinated actions of HRG-1 heme permeases to transport environmental heme into the intestine and HRG-3, a secreted protein, to deliver intestinal heme to other tissues including the embryo. Here we show that heme homeostasis in the extraintestinal hypodermal tissue was facilitated by the transmembrane protein HRG-2. Systemic heme deficiency up-regulated hrg-2 mRNA expression over 200-fold in the main body hypodermal syncytium, hyp 7. HRG-2 is a type I membrane protein that binds heme and localizes to the endoplasmic reticulum and apical plasma membrane. Cytochrome heme profiles are aberrant in HRG-2-deficient worms, a phenotype that was partially suppressed by heme supplementation. A heme-deficient yeast strain, e

SUBMITTER: Chen C 

PROVIDER: S-EPMC3308796 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature