The MTCP-1/c6.1B gene encodes for a cytoplasmic 8 kD protein overexpressed in T cell leukemia bearing a t(X;14) translocation

Oncogene. 1994 Dec;9(12):3565-70.


The t(X;14)(q28;q11.2) translocation is associated with mature T-cell proliferations. Recently this translocation has been shown to implicate the MTCP-1/c6.1B gene on chromosome Xq28, leading to aberrant or overexpressed MTCP-1 transcripts. The potential coding role of this gene was made uncertain by the lack of a long open reading frame in its major transcripts. However, a short 204 bases open reading frame is potentially coding for a 68 amino-acid protein. Here, we show that this open reading frame sequence and the deduced product are well conserved in mouse. A 8 kD protein (p8), which corresponds to the predicted molecular weight was revealed in transient transfectants and in cell lines by Western blotting, using a rabbit antiserum. This product was absent in lymphoblastoid cell lines with deletions of the MTCP-1/c6.1B locus. A dramatic overexpression of p8 was found in leukemic cells from a patient with a t(X;14). This small protein was localized in the cytoplasm by immunofluorescence. In conclusion, MTCP-1 encodes for a cytoplasmic 8 kD product. Its potential role in leukemogenesis is supported by its overexpression in leukemia with t(X;14), but its function remains unknown.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Chromosomes, Human, Pair 14*
  • Cytoplasm / metabolism
  • DNA, Complementary
  • Humans
  • Immune Sera
  • Leukemia, T-Cell / genetics*
  • Leukemia, T-Cell / metabolism
  • Mice
  • Molecular Sequence Data
  • Neoplasm Proteins / genetics*
  • Oncogenes
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / immunology
  • Translocation, Genetic*
  • Tumor Cells, Cultured
  • X Chromosome*


  • DNA, Complementary
  • Immune Sera
  • MTCP1 protein, human
  • Neoplasm Proteins
  • Proto-Oncogene Proteins

Associated data

  • GENBANK/Z35294