The C-terminal domain of the regulatory protein NOVH is sufficient to promote interaction with fibulin 1C: a clue for a role of NOVH in cell-adhesion signaling.

The NOVH protein belongs to the emerging CCN [Connective tissue growth factor (CTGF), Cyr61/Cef10, nephroblastoma overexpressed gene] family of growth regulators sharing a strikingly conserved multimodular organization but exhibiting distinctive functional features. Two members of the family (CYR61 and CTGF) are positive regulators of cell proliferation, whereas NOVH and two other members (ELM1 and RCOP-1) exhibit features of negative regulators of growth. The multimodular structure of these proteins suggests that their biological role(s) may depend on interactions with several factors as well as proteins constitutive of the extracellular matrix. To gain insight into the functionality of these domains, we have used a two-hybrid system to identify proteins interacting with NOVH. We report here that the C-terminal domain confers on the full-length NOVH protein the capacity to bind fibulin 1C, a protein of the extracellular matrix that interacts with several other regulators of cell adhesion. Furthermore, we show that a natural N-truncated isoform of NOVH produced by cells expressing the full-length NOVH protein also binds fibulin 1C with a high affinity, and we hypothesize that the production of truncated isoforms of NOVH (and probably of other CCN proteins) may be a critical aspect in the modulation of their biological activity. These results set the stage for a study of NOVH-fibulin 1C interactions and their potential significance in cell-adhesion signaling in normal and pathological conditions.

[1]  M. Somerman,et al.  Fibulin is an extracellular matrix and plasma glycoprotein with repeated domain structure , 1990, The Journal of cell biology.

[2]  L. Lau,et al.  Expression of the growth factor-inducible immediate early gene cyr61 correlates with chondrogenesis during mouse embryonic development. , 1992, Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research.

[3]  R. Timpl,et al.  The extracellular matrix glycoproteins BM-90 and tenascin are expressed in the mesenchyme at sites of endothelial-mesenchymal conversion in the embryonic mouse heart. , 1993, Differentiation; research in biological diversity.

[4]  H. Hanafusa,et al.  Transcriptional down regulation of the nov proto-oncogene in fibroblasts transformed by p60v-src , 1996, Molecular and cellular biology.

[5]  P. A. Harding,et al.  Characterization of cell-associated and soluble forms of connective tissue growth factor (CTGF) produced by fibroblast cells in vitro. , 1998, Growth factors.

[6]  R. Timpl,et al.  Fibulin‐1 and fibulin‐2 expression during organogenesis in the developing mouse embryo , 1996, Developmental dynamics : an official publication of the American Association of Anatomists.

[7]  L. Lau,et al.  Expression of cyr61, a growth factor-inducible immediate-early gene , 1990, Molecular and cellular biology.

[8]  W. Hendrickson,et al.  A structural superfamily of growth factors containing a cystine knot motif , 1993, Cell.

[9]  高野 加寿恵,et al.  Molecular mechanisms to regulate the activities of insulin-like growth factors : proceedings of the 4th International Symposium on Insulin-like Growth Factors, at Tokyo International Forum, Tokyo, Japan, 21-24 October 1997 , 1998 .

[10]  B. Perbal.  Contribution of MAV-1-induced nephroblastoma to the study of genes involved in human Wilms' tumor development. , 1994, Critical reviews in oncogenesis.

[11]  B. Perbal,et al.  A developmental study of novH gene expression in human central nervous system. , 1998, Comptes rendus de l'Academie des sciences. Serie III, Sciences de la vie.

[12]  Z. Ruggeri,et al.  von Willebrand factor. , 1997, The Journal of clinical investigation.

[13]  E. Viégas-Péquignot,et al.  Chromosomal mapping and expression of the human cyr61 gene in tumour cells from the nervous system. , 1997, Molecular pathology : MP.

[14]  P. Schofield,et al.  novH: differential expression in developing kidney and Wilm's tumors. , 1998, The American journal of pathology.

[15]  R. Coffey,et al.  Identification of rCop-1, a New Member of the CCN Protein Family, as a Negative Regulator for Cell Transformation , 1998, Molecular and Cellular Biology.

[16]  B. Perbal,et al.  Regulation of nov by WT1: a potential role for nov in nephrogenesis. , 1996, Oncogene.

[17]  P. Bork.  The modular architecture of a new family of growth regulators related to connective tissue growth factor , 1993, FEBS letters.

[18]  Gary R. Grotendorst,et al.  Connective tissue growth factor: a cysteine-rich mitogen secreted by human vascular endothelial cells is related to the SRC-induced immediate early gene product CEF-10 , 1991, The Journal of cell biology.

[19]  L. Strong,et al.  Structural analysis of the human nov proto-oncogene and expression in Wilms tumors , 1994 .

[20]  L. Woodhead.  A Practical Guide to Molecular Cloning , 1985 .

[21]  W. Argraves,et al.  The Self-association and Fibronectin-binding Sites of Fibulin-1 Map to Calcium-binding Epidermal Growth Factor-like Domains* , 1997, The Journal of Biological Chemistry.

[22]  R. Timpl,et al.  Sequence of extracellular mouse protein BM-90/fibulin and its calcium-dependent binding to other basement-membrane ligands. , 1993, European journal of biochemistry.

[23]  S. Spence,et al.  Fibulin is localized at sites of epithelial-mesenchymal transitions in the early avian embryo. , 1992, Developmental biology.

[24]  C. Haudenschild,et al.  The Interaction of Fibulin-1 with Fibrinogen , 1995, The Journal of Biological Chemistry.

[25]  L. Lau,et al.  Cyr61, a product of a growth factor-inducible immediate-early gene, promotes cell proliferation, migration, and adhesion , 1996, Molecular and cellular biology.

[26]  M. Mattei,et al.  Structure, mapping, and expression of fisp-12, a growth factor-inducible gene encoding a secreted cysteine-rich protein. , 1991, Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research.

[27]  D. Levy,et al.  Identification of a phorbol ester-repressible v-src-inducible gene. , 1989, Proceedings of the National Academy of Sciences of the United States of America.

[28]  D. Strickland,et al.  Fibulin binds to itself and to the carboxyl-terminal heparin-binding region of fibronectin. , 1992, Journal of Biological Chemistry.

[29]  V. Joliot,et al.  Proviral rearrangements and overexpression of a new cellular gene (nov) in myeloblastosis-associated virus type 1-induced nephroblastomas , 1992, Molecular and cellular biology.

[30]  M. Westphal,et al.  Differential expression of novH and CTGF in human glioma cell lines , 1996, Clinical molecular pathology.

[31]  M. Binoux,et al.  A proteolytic fragment of insulin-like growth factor (IGF) binding protein-3 that fails to bind IGFs inhibits the mitogenic effects of IGF-I and insulin. , 1996, Endocrinology.

[32]  J. Yokota,et al.  Expression of the Elm1 Gene, a Novel Gene of the CCN (Connective Tissue Growth Factor, Cyr61/Cef10, and Neuroblastoma Overexpressed Gene) Family, Suppresses In Vivo Tumor Growth and Metastasis of K-1735 Murine Melanoma Cells , 1998, The Journal of experimental medicine.