The mammalian single-minded (sim) gene: Mouse cdna structure and specific expression in diencephalon

Nobuvoshi Shimizu, Akiko Yamaki, Setsuko Noda, Nobuaki Shindoh, Hideto Maeda, Yoshiko Shimizu, Shinsei Minoshima, Jun Kudoh

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To isolate genes potentially involved in the pathogenesis of Down syndrome, we recently performed exon trapping experiments using a series of cosmid clones derived from the DSCR (CBR-D21S55-ERG) and found six exons which have a striking sequence homology with the Drosophila single-minded (sim) gene [Nature Genetics, 10: 9-10 (1995)]. The Drosophila sim gene encodes a transcription factor which regulates the development of central nervous system midline cell lineage, and thus the identification of a human homolog (hSIM) from the DSCR is quite intriguing. We have now isolated SIM cDNA clones from a mouse embryo cDNA library. Mouse SIM protein is highly homologous to human SIM and Drosophila Sim proteins, all contain the basic-helix-loop-helix (bHLH) domain and the PAS domain. In situ hybridization analysis indicated that SIM is expressed in the diencephalon of mouse embryos at the age of 8-9.5 days postcoitum. These results strongly suggest that the newly isolated mammalian SIM homolog functions as a transcriptional regulator which plays a critical role in the development of the central nervous system. The hSIM gene may potentially be involved in the pathogenesis of Down syndrome.

Original languageEnglish
Number of pages1
JournalJapanese Journal of Human Genetics
Issue number1
Publication statusPublished - 1996 Dec 1


ASJC Scopus subject areas

  • Genetics(clinical)

Cite this

Shimizu, N., Yamaki, A., Noda, S., Shindoh, N., Maeda, H., Shimizu, Y., Minoshima, S., & Kudoh, J. (1996). The mammalian single-minded (sim) gene: Mouse cdna structure and specific expression in diencephalon. Japanese Journal of Human Genetics, 41(1).