The primary interest of my laboratory is to understand the molecular and cellular mechanisms that control vertebrate embryogenesis, with particular focus on identifying signals that direct the development of the musculoskeletal system from a group of mesodermal structures called somites. Under the influence of signals supplied by surrounding tissues, somites differentiate into tissues that give rise to cartilage, dermis, and limb and axial muscle. An in vitro assay system is used to investigate the early events of mouse somite development: the formation of sclerotome (precursor of vertebrae and ribs), dermomyotome (precursor of dermis and limb muscle) and myotome (precursor of axial muscle). In this assay, various tissues isolated from the mouse embryos were co cultured with presomitic mesoderm (precursor to somites) in three-dimensional collagen gels to test their ability to induce specific cell types in the presomitic mesoderm. This system allows the identification of not only the specific inducer tissues but also the cellular mechanisms of these tissue interactions employed to establish the proper somitic pattern. Using this system, Sonic Hedgehog (SHH) expressed in the notochord and floorplate was identified as a diffusible molecule that induces sclerotome differentiation. However, molecular identities of the diffusible signal(s) emanating from neural tube that induces myotome and the contact-dependent signal (s) resides on the surface ectoderm membrane that elicits dermomyotomal fate are not yet defined.

The immediate goal of my laboratory is to use various complementary strategies to identify molecules that pattern the dermomyotome and myotome. The identification of all these factors will make it possible to analyze the molecular basis of somite patterning and the differentiation program of muscle, dermis and bone. The long term goals are to identify and study these patterning factors, their signaling pathways and their downstream target genes that control these processes at the molecular level by functional assays. Information contained from these in vitro studies will be utilized to design experiments to assess the function of these molecules in somite differentiation by genetic manipulations in the mouse including homologous recombination and transgenic ectopic expression systems.

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Fan, C.-M. and Maniatis, T. (1989). Two different virus-inducible elements are required for beta-interferon gene regulation. EMBO J. 8, 101-110.

Lenardo, M.J., Fan, C.-M., Maniatis, T. and Baltimore, D. (1989). The involvement of NF-kappa-B in beta-interferon gene regulation reveals its role as widely inducible mediator of signal transduction. Cell 57, 287-294.

Fan, C.-M. and Maniatis, T. (1990). A DNA binding protein containing two widely separated zinc finger motifs that recognize the same DNA sequence. Genes & Development 4, 29-42.

Fan, C.-M. and Maniatis, T. (1991). The p50 subunit of NF-kappa-B is generated by processing of p105 through an ATP-dependent pathway. Nature 354, 395-398.

Maniatis, T., Whittemore, L.-A., Du, W., Fan, C.-M., Keller, A., Palombella, V.J. Thanos, D.N. (1992). Positive and Negative Control of Human Interferon- Gene Expression. Harvey Lecture 44, 1193-1220. Cold Spring Harbor Press.

Fan, C.-M. and Tessier-Lavigne, M. (1994). Patterning of Mammalian Somites by the Surface Ectoderm and the Notochord: Evidence for Sclerotome Induction by a Hedgehog Homolog. Cell 79, 1175-1186.

Fan, C.-M., Porter, J., Chiang, C., Chang, D.T., Beachy, P.A., and Tessier-Lavigne, M. (1995). Long-Range Sclerotome Induction by Sonic Hedgehog: Direct Role of the Amino-Terminal Cleavage Product and Modulation by the cyclic-AMP Signaling Pathway. Cell 81, 457-465.

Muenke, M., Bone, L., Mitchell, H., Hart, I., Walton, K., Hall-Johnson, K., Ippel. E., Dietz-Band, J., Karloy, K., Fan, C.-M., Tessier-Lavigne, M., and Patterson, D. (1995). Physical Mapping of the Holoprosencephaly Critical Region in 21q22.3, Exclusion of SIM2 as a Candidate Gene for HPE, and Mapping of SIM2 to a Region of Chromosome 21 Important for Down Syndrome. The American Journal of Human Genetics 57, 1074-1079

Pourquie, O., Fan, C.-M., Coltey, M., Hirsinger, E., Watanabe, Y., Breant, C., Francis-West, P., Brickell, P., Tessier-Lavigne, M., and Le Douarin, N.M. (1996). Lateral and Axial Signals involved in Avian Somite Patterning : Role of the BMP4 Protein. Cell 84, 461-471.

Fan, C.-M., Kuwana, E., Bulfone, A., Fletcher, C. F., Copeland, N. G., Jenkins, N. A., Crews, S., Salvador, M., Puelles, L., Rubenstein, J. L. R., and Tessier-Lavigne, M. (1996). Expression Patterns of Two Murine Homologs of Drosophila single-minded Suggest Possible Roles in Embryonic Patterning and in the Pathogenesis of Down Syndrome. Molecular and Cellular Neuroscience 7, 1-16.

Mastick, G.S., Fan, C.-M., Tessier-Lavigne, M., Serbedzija, G.N., MaMahon, A.P., Easter, S.S., Jr. (1996). Early Deletion of Neuromeres in Wnt-1-/- Mutant Mice: Evaluation by Morphological and Molecular Markers. The Journal of Comparative Neurology 374, 246-258.

Probst, M.R., Fan, C.-M.,Tessier-Lavigne, M., and Hankinson, O. (1997). Two Murine Homologs of the Drosophila single-minded Protein that Interact with the Mouse Aryl Hydrocarbon Receptor Nuclear Translocator Protein. Journal of Biological Chemistry 272, 4451-4457.

Michaud, J. and Fan, C.-M. (1997). Single-minded - Two Genes, Three Chromosomes. Genome Research 7, 569-571.

Fan, C.-M., Lee, C.S., and Tessier-Lavigne, M. (1997) A Role for WNT Proteins in Induction of Dermomyotome. Developmental Biology 191, 160-165.

McMahon, J., Takada, S., Zimmerman, L.B., Fan, C.-M., Harland, R.M., and McMahon, A.P. (1998) Noggin-mediated antagonism of BMP signaling is required for growth and patterning of the neural tube and somite. Genes & Development 12, 1438-1452.

Michaud, J., Rosenquist, T., May, N.R., and C.-M. Fan. (1998). Development of neuroendocrine lineages requires the BHLH-PAS transcription factor SIM1. Genes & Development 12, 3264-3275.

Lee, C.S., Buttitta, L., May, N.R., Kispert, A., and C.-M. Fan. (2000). SHH-N upregulates Sfrp2 in the somitic mesoderm to mediate its competitive action with WNT1 and WNT4. Development 127, 109-118.

Michaud, J.L., De Rossi, C., May, N.R., Holdener, B., and C.-M. Fan. (2000). ARNT2 acts as the dimerization partner of SIM1 for the development of the hypothalamus. Mechanism of Development 90, 253-261.

Epstein, D.J., Martinu, L., Michaud, J.L., Losos, K.M., Fan, C.-M., and A.-L. Joyner. (2000). Members of the bHLH-PAS family regulate Shh transcription in forebrain regions of the mouse CNS.
Development 127, 4701-4709.

Lee, S.C. and C.-M. Fan. (2001). Embryonic expression patterns of the mouse and chick Gas1 genes. Mechanism of Development 101, 293-297.

Lee, C.S., May, N.R., and C.-M. Fan. (2001). Transdifferentiation of the ventral retinal pigmented epithelium to neural retina in the Graowth Arrest Specific Gene 1 mutant. Developmental Biology 236, 17-29.

Liu, Y., May, N.R., C.-M. Fan. (2001). Growth Arrest Specific Gene 1 is a positive growth regulator for the cerebellum. Developmental Biology 236, 30-45.

Lee, C.S., Buttitta, L., and C.-M. Fan. (2001). Evidence that the WNT-inducible growth arrest specific gene 1 encodes an antagonist of sonic hedgehog signaling in the somite. Proc. Natl. Acad. Sci. USA 98, 11347-11352.

Michaud, J.L., Boucher, F., Melnyk, A., Gauthier, F, Goshu, E., Levy, E., Mitchell, G.A., Himms-Hagen, J., and C.-M. Fan. (2001). Human Molecular Genetics 10, 1465-1473.

Goshu, E. Jin, H., Fasnacht, R., Spenski, M., Michaud, J.L., and C.-M. Fan. (2002). Sim2 mutants have developmental defects not overlapping with those of Sim1 mutants. Mol.Cell. Biol. 22, 4147-4157.

Liu, Y., Liu, C., Yamada, Y., and C.-M. Fan. (2002). Growth arrest specific gene 1 acts as a region-specific mediator of the Fgf10/Fgf8 regulatory loop in the limb. Development 129, 5289-5300.

Buttitta, L., Tanaka, T., Chen, A., Ko, M., and C.-M. Fan. (2003) Microarray analysis reveals novel WNT targets in the somites. Developmental Biology 258, 91-104.

Liu C, Goshu E, Wells A, Fan CM. (2003) Identification of the downstream targets of SIM1 and ARNT2, a pair of transcription factors essential for neuroendocrine cell differentiation. J Biol Chem. 278:44857-67.

Buttitta L, Mo R, Hui CC, Fan CM. (2003) Interplays of Gli2 and Gli3 and their requirement in mediating Shh-dependent sclerotome induction. Development 130:6233-43.

Goshu E, Jin H, Lovejoy J, Marion JF, Michaud JL, Fan CM. (2004) Sim2 contributes to neuroendocrine hormone gene expression in the anterior hypothalamus. Mol Endocrinol. 18:1251-62. 

Chen AE, Ginty DD, Fan CM. (2005) Protein kinase A signalling via CREB controls myogenesis induced by Wnt proteins. Nature 433: 208-9.

Chen AE, Fan CM. (2005) Targeting gene expression in the mouse somite: adenovirus-mediated gene delivery and whole embryo culture. Genesis 42:71-6.

Martinelli DE, Fan CM (2007) Gas1 extends the range of Hedgehog action by facilitating its signaling. Genes Dev 2007 May 15;21(10):1231-43.

Xu C, Fan CM (2007) Allocation of paraventricular and supraoptic neurons requires Sim1 function: a role for a Sim1 downstream gene PlexinC1. Mol Endocrinol 2007 May; 21(5):1234-45.

Maisa Seppala, Michael J. Depew, David C. Martinelli, Chen-Ming Fan, Paul T. Sharpe and Martyn T. Cobourne (2007) Gas1 is a modifier for holoprosencephaly and genetically interacts with sonic hedgehog. J Clin Invest 2007 Jun;117(6):1575-84.

Martinelli DE, Fan CM (2007) The Role of Gas1 in Embryonic Development and its Implications for Human Disease. Cell Cycle 2007 Aug 13; 6(21).

Friedman ER, Fan CM. (2007) Separate necdin domains bind ARNT2 and HIF1alpha and repress transcription. Biochem Biophys Res Commun 363, 113-118.

Xu, C. and Fan, C.-M. (2007) Allocation of paraventricular and supraoptic neurons requires Sim1 function: a role for a Sim1 downstream gene PlexinC1. Molecular Endocrinology 21, 1234-1245.

Martinelli, D.C. and Fan, C.-M. (2007) Gas1 extends the range of Hedgehog action by facilitating its signaling. Genes & Development 15, 1231-1243.

Seppala, M., Depew, M.J., Martinelli, D.C., Fan, C.-M., Sharpe P.T., and Cobourne M.T. (2007) Gas1 is a modifier for holoprosencephaly and genetically interacts with sonic hedgehog. Journal of Clinical Investigation 117, 1575-1584.

Martinelli, D.C. and Fan, C.M. (2007) The role of Gas1 in embryonic development and its implications for human disease. Cell Cycle 6, 2650-2655.

Friedman, E.R. and Fan, C.-M. (2007) Separate Necdin domains bind ARNT2 and HIF1a and repress transcription. Biochemical Biophysical Research Communications 63, 113-118.

Xu, C. and Fan, C.-M. (2008) Neuropilin, Plexin, and Semaphorin family members are expressed in the developing hypothalamus. Gene expression patterns 8, 502-507.

Zhang, Y., Narayan, S., Geiman, E., Lanuza, G. M., Velasquez, T., Shanks, B., Akay, T., Dyck, J., Pearson, K., Gosgnach, S., Fan, C.-M., and Goulding, M. (2008) V3 spinal neurons establish a robust and balanced locomotor rhythm during walking Neuron 60, 84-95.

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