The Caenorhabditis elegans homologue of Down syndrome critical region 1, RCN-1, inhibits multiple functions of the phosphatase calcineurin

J Mol Biol. 2003 Apr 18;328(1):147-56. doi: 10.1016/s0022-2836(03)00237-7.


A conserved family of calcineurin-regulating proteins whose members have been implicated in several disease models such as Down syndrome, Alzheimer's disease, and cardiac hypertrophy has been identified in several organisms including yeast, mice, and humans. We have characterized Caenorhabditis elegans rcn-1, which belongs to this family of calcineurin regulators, and shows approximately 40% identity with the human homologue DSCR-1. rcn-1 is expressed in hypodermal cells, nerve cords and various neurons, vulva epithelial and muscle cells, marginal cells of the pharynx, and structures of the male tail. rcn-1 expression is upregulated by calcineurin activity. RCN-1 binds to calcineurin A from C.elegans lysate in a calcium-dependent manner, and inhibits bovine calcineurin phosphatase activity dose-dependently. In addition, overexpression of RCN-1 results in calcineurin-deficient phenotypes such as small body size, cuticle defects, fertility defects, slow growth, and serotonin-resistant egg-laying defects. Moreover, phenotypes observed in gain-of-function calcineurin mutant animals were restored to normal by RCN-1 overexpression. These results demonstrate an effective and specific inhibition of calcineurin in vitro as well as in vivo by RCN-1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans Proteins / genetics*
  • Caenorhabditis elegans Proteins / metabolism*
  • Caenorhabditis elegans Proteins / pharmacology
  • Calcineurin / metabolism
  • Calcineurin Inhibitors*
  • Cloning, Molecular
  • DNA-Binding Proteins
  • Down Syndrome
  • Enzyme Inhibitors / metabolism
  • Enzyme Inhibitors / pharmacology
  • Gene Expression Regulation
  • Green Fluorescent Proteins
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Luminescent Proteins / genetics
  • Male
  • Muscle Proteins / genetics*
  • Muscle Proteins / metabolism*
  • Muscle Proteins / pharmacology
  • Muscles / physiology
  • Neurons / metabolism
  • Pharynx / physiology
  • Phenotype
  • Recombinant Fusion Proteins / biosynthesis
  • Recombinant Fusion Proteins / genetics
  • Tail / physiology


  • Caenorhabditis elegans Proteins
  • Calcineurin Inhibitors
  • DNA-Binding Proteins
  • Enzyme Inhibitors
  • Intracellular Signaling Peptides and Proteins
  • Luminescent Proteins
  • Muscle Proteins
  • RCAN1 protein, human
  • RCN-1 protein, C elegans
  • Recombinant Fusion Proteins
  • Green Fluorescent Proteins
  • Calcineurin