A new human nm23 homologue (nm23-H5) specifically expressed in testis germinal cells

FEBS Lett. 1998 Sep 4;434(3):289-94. doi: 10.1016/s0014-5793(98)00996-x.


We have identified a cDNA encoding a 212 amino acid protein (Nm23-H5) with 27-31% identity to the human members of the nm23/nucleoside diphosphate (NDP) kinase gene family. The nm23-H5 gene is located on chromosome 5q23-31 and is transcribed as one main transcript of 1.1 kb which is highly and specifically expressed in testis, in the spermatogonia and early spermatocytes. Nm23-H5 possesses most of the residues conserved among NDP kinases plus an additional COOH-terminus end of 55 amino acids unique to this protein. However, under usual assay conditions, Nm23-H5 expressed in Escherichia coli did not exhibit NDP kinase activity. These results suggest that Nm23-H5 is specifically involved in early stages of spermatogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Chromosome Mapping
  • Chromosomes, Human, Pair 5
  • Cloning, Molecular
  • DNA Primers
  • DNA, Complementary
  • Histones / genetics*
  • Humans
  • In Situ Hybridization
  • Male
  • Molecular Sequence Data
  • Monomeric GTP-Binding Proteins*
  • NM23 Nucleoside Diphosphate Kinases
  • Nucleoside-Diphosphate Kinase / metabolism
  • Polymerase Chain Reaction
  • RNA, Messenger / genetics
  • Sequence Homology, Amino Acid
  • Spermatozoa / metabolism*
  • Testis / cytology
  • Testis / metabolism*
  • Transcription Factors / genetics*


  • DNA Primers
  • DNA, Complementary
  • Histones
  • NM23 Nucleoside Diphosphate Kinases
  • NME5 protein, human
  • RNA, Messenger
  • Transcription Factors
  • NME1 protein, human
  • Nucleoside-Diphosphate Kinase
  • Monomeric GTP-Binding Proteins

Associated data

  • GENBANK/Y14992