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Nuclear localization of GDF‐5
Author(s) -
Jensen J. Daniel,
Felin Jenny E.,
Meinhart Christopher,
Bridgewater Laura C.
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.4.a545-a
Subject(s) - nuclear localization sequence , growth differentiation factor , microbiology and biotechnology , bone morphogenetic protein , nuclear protein , transcription factor , biology , chondrogenesis , cleavage (geology) , cell nucleus , cellular differentiation , nucleus , genetics , gene , stem cell , paleontology , fracture (geology)
Growth and differentiation factor‐5 (GDF‐5) has been shown to promote chondrogenesis and osteogenesis during development and tissue repair. A member of the transforming growth factor‐beta (TGF‐beta) superfamily, it is closely related to the bone morphogenic protein (BMP) subfamily. Like BMP‐2, GDF‐5 undergoes proteolytic cleavage prior to secretion of the mature peptide from the cell. Although traditionally regarded solely as an extracellular signaling protein, a yeast one‐hybrid screen recently identified GDF‐5 as a possible DNA‐binding protein in chondrocytic cells. Upon further investigation, a putative nuclear localization signal (NLS)—homologous with that recently discovered in BMP‐2—was identified. The NLS overlaps the site of proteolytic cleavage, suggesting that an uncleaved variant of GDF‐5 may be localized to the nucleus. Immunohistochemical analysis of rat chondrosarcoma (RCS) cells revealed that GDF‐5 is, in fact, detectable in the nuclei of some cells. Further characterization of the nuclear variant of GDF‐5 is ongoing. The discovery of GDF‐5 in the nuclei of RCS cells suggests a novel role for this protein in the direct regulation of transcription during cartilage differentiation. This work was supported by NIH grant #RO1‐AR048839.