Molecular cloning of Ian4: a BCR/ABL-induced gene that encodes an outer membrane mitochondrial protein with GTP-binding activity

Nucleic Acids Res. 2001 Mar 15;29(6):1308-16. doi: 10.1093/nar/29.6.1308.


Using the representation difference analysis technique, we have identified a novel gene, Ian4, which is preferentially expressed in hematopoietic precursor 32D cells transfected with wild-type versus mutant forms of the Bcr/Abl oncogene. Ian4 expression was undetectable in 32D cells transfected with v-src, oncogenic Ha-ras or v-Abl. Murine Ian4 maps to chromosome 6, 25 cM from the centromere. The Ian4 mRNA contains two open reading frames (ORFs) separated by 5 nt. The first ORF has the potential to encode for a polypeptide of 67 amino acids without apparent homology to known proteins. The second ORF encodes a protein of 301 amino acids with a GTP/ATP-binding site in the N-terminus and a hydrophobic domain in the extreme C-terminus. The IAN-4 protein resides in the mitochondrial outer membrane and the last 20 amino acids are necessary for this localization. The IAN-4 protein has GTP-binding activity and shares sequence homology with a novel family of putative GTP-binding proteins: the immuno-associated nucleotide (IAN) family.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Line
  • Chromosome Mapping
  • Cloning, Molecular
  • Crosses, Genetic
  • DNA, Complementary / chemistry
  • DNA, Complementary / genetics
  • Female
  • Fusion Proteins, bcr-abl / genetics
  • Fusion Proteins, bcr-abl / physiology
  • GTP-Binding Proteins / genetics*
  • GTP-Binding Proteins / metabolism
  • Gene Expression Regulation
  • Haplotypes
  • Humans
  • Intracellular Membranes / metabolism
  • K562 Cells
  • Male
  • Membrane Proteins / genetics*
  • Membrane Proteins / metabolism
  • Mice
  • Microscopy, Confocal
  • Mitochondria / metabolism*
  • Molecular Sequence Data
  • RNA / genetics
  • RNA / metabolism
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Tumor Cells, Cultured


  • DNA, Complementary
  • Ian3 protein, mouse
  • Ian4 protein, mouse
  • Membrane Proteins
  • RNA
  • Fusion Proteins, bcr-abl
  • GTP-Binding Proteins

Associated data

  • GENBANK/AF337052