The mouse Nkx-1.2 homeobox gene: alternative RNA splicing at canonical and noncanonical splice sites

Proc Natl Acad Sci U S A. 2000 Feb 29;97(5):1982-7. doi: 10.1073/pnas.030539397.


A mouse homeobox gene, Nkx-1.2, (previously termed Sax-1) that is closely related to the Drosophila NK-1/S59 gene was cloned, and genomic DNA and cDNA were sequenced. Nine Nkx-1.2 cDNA clones were found that correspond to three species of Nkx-1.2 mRNA that are formed by alternative splicing at conventional 5' donor and 3' acceptor splice sites; however, seven cDNA clones were found that correspond to three species of Nkx-1.2 mRNA from testes that have novel TG/AC 5' and 3' splice sites. The consensus splice sequences are: 5' donor, CC downward arrowTGGAAG; 3' acceptor, ACTTAC downward arrow. Predicted amino acid sequences suggest that some transcripts may be translated into proteins that lack part or all of the homeodomain. At least three bands of Nkx-1.2 mRNA were found in RNA from the testes. Nkx-1.2 mRNA was shown to be present in postmeiotic germ cells of the testis and in mature spermatozoa. Nkx-1.2 mRNA also was found in regions of the adult cerebral cortex, hippocampus, diencephalon, pons/medulla, and cerebellum. Nkx-1.2 mRNA was found in embryos in highest abundance in 10-day embryos; the mRNA levels decrease during further development. Nkx-1.2 mRNA also was found in discrete zones of the embryonic mesencephalon and myelencephalon.

MeSH terms

  • Alternative Splicing*
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Brain / pathology
  • Chromosome Mapping
  • Cloning, Molecular
  • DNA, Complementary
  • Female
  • Gene Expression
  • Homeodomain Proteins / genetics*
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Molecular Sequence Data
  • Nuclear Proteins*
  • RNA, Messenger
  • Sequence Homology, Amino Acid
  • Spermatozoa
  • Transcription Factors*


  • DNA, Complementary
  • Homeodomain Proteins
  • Nkx1-2 protein, mouse
  • Nuclear Proteins
  • RNA, Messenger
  • Transcription Factors

Associated data

  • GENBANK/AF222442
  • GENBANK/AF222443
  • GENBANK/AF222444
  • GENBANK/AF222445
  • GENBANK/AF223361
  • GENBANK/AF223362
  • GENBANK/AF223363
  • GENBANK/AF223674
  • GENBANK/AF223675