ALEX1, a novel human armadillo repeat protein that is expressed differentially in normal tissues and carcinomas

Biochem Biophys Res Commun. 2001 Jan 12;280(1):340-7. doi: 10.1006/bbrc.2000.4125.


Members of the armadillo (arm) repeat family of proteins are implicated in tumorigenesis, embryonic development, and maintenance of tissue integrity. We have cloned cDNA for a novel human arm repeat protein, ALEX1, encoding 453 amino acids. ALEX1 shares significant homology with uncharacterized ORF KIAA0512 and putative protein product of unknown mRNA (GenBank AF211175), designated here as ALEX2 and ALEX3, respectively. The genes encoding ALEX1, ALEX2 and ALEX3 co-localize to the same region in Xq21.33-q22.2. ALEX1 and ALEX2 transcripts are found in all human tissues examined except peripheral blood leukocytes. Expression of ALEX1 and ALEX2 mRNA is lost or significantly reduced in human lung, prostate, colon, pancreas, and ovarian carcinomas and also in cell lines established from different human carcinomas. These genes are, however, normally expressed in cell lines derived from other types of tumors, e.g., sarcomas, neuroblastomas, and gliomas. We speculate that ALEX genes may play a role in suppression of tumors originating from epithelial tissue, i.e., carcinomas.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Armadillo Domain Proteins
  • Base Sequence
  • Chromosome Mapping
  • Drosophila
  • Drosophila Proteins*
  • Female
  • Gene Library
  • Humans
  • Insect Proteins / chemistry
  • Insect Proteins / genetics
  • Male
  • Molecular Sequence Data
  • Neoplasms / genetics
  • Oncogene Proteins / chemistry
  • Oncogene Proteins / genetics*
  • Organ Specificity
  • Phylogeny
  • Pregnancy
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Testis / metabolism
  • Trans-Activators*
  • Transcription Factors
  • Transcription, Genetic
  • Tumor Cells, Cultured
  • X Chromosome*


  • ARM protein, Drosophila
  • ARMCX1 protein, human
  • Armadillo Domain Proteins
  • Drosophila Proteins
  • Insect Proteins
  • Oncogene Proteins
  • Trans-Activators
  • Transcription Factors

Associated data

  • GENBANK/AB039669
  • GENBANK/AB039670