3pK, a new mitogen-activated protein kinase-activated protein kinase located in the small cell lung cancer tumor suppressor gene region.

Academic Article


  • NotI linking clones, localized to the human chromosome 3p21.3 region and homozygously deleted in small cell lung cancer cell lines NCI-H740 and NCI-H1450, were used to search for a putative tumor suppressor gene(s). One of these clones, NL1G210, detected a 2.5-kb mRNA in all examined human tissues, expression being especially high in the heart and skeletal muscle. Two overlapping cDNA clones containing the entire open reading frame were isolated from a human heart cDNA library and fully characterized. Computer analysis and a search of the GenBank database to reveal high sequence identity of the product of this gene to serine-threonine kinases, especially to mitogen-activated protein kinase-activated protein kinase 2, a recently described substrate of mitogen-activated kinases. Sequence identitiy was 72% at the nucleotide level and 75% at the amino acid level, strongly suggesting that this protein is a serine-threonine kinase. Here we demonstrate that the new gene, referred to as 3pK (for chromosome 3p kinase), in fact encodes a mitogen-activated protein kinase-regulated protein serine-threonine kinase with a novel substrate specificity.
  • Published In


  • Amino Acid Sequence, Base Sequence, Carcinoma, Small Cell, Cloning, Molecular, DNA, Complementary, Genes, Tumor Suppressor, Humans, Intracellular Signaling Peptides and Proteins, Lung Neoplasms, Molecular Sequence Data, Protein-Serine-Threonine Kinases, Sequence Alignment
  • Author List

  • Sithanandam G; Latif F; Duh FM; Bernal R; Smola U; Li H; Kuzmin I; Wixler V; Geil L; Shrestha S
  • Start Page

  • 868
  • End Page

  • 876
  • Volume

  • 16
  • Issue

  • 3