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Growth differentiation factor 11 (GDF11) also known as bone morphogenetic protein 11 (BMP-11) is a protein that in humans is encoded by the ''GDF11'' gene. This BMP group of proteins is characterized by a polybasic proteolytic processing site, which is cleaved to produce a protein containing seven conserved cysteine residues.〔(【引用サイトリンク】url=http://www.genecards.org/cgi-bin/carddisp.pl?gene=GDF11 )〕 GDF11 is a myostatin-homologous protein that acts as an inhibitor of nerve tissue growth. GDF11 has been shown to suppress neurogenesis through a pathway similar to that of myostatin, including stopping the progenitor cell-cycle during G-phase. The similarities between GDF11 and myostatin imply a likelihood that the same regulatory mechanisms are used to control tissue size during both muscular and neural development.〔 In 2014, GDF11 was described as an anti-aging factor in two publications based on the results of a parabiosis experiments with mice that were chosen as ''Science's'' scientific breakthrough of the year.〔http://www.thecherrycreeknews.com/young-blood-reverses-aging-breakthrough-2014-gdf11/〕 Later studies questioned these findings. Researchers disagree on the selectivity of the tests used to measure GDF11 and on the activity of GDF11 from various commercially-available sources. The full relationship of GDF11 to aging—and any possible differences in the action of GDF11 in mice, rats, and humans—is unclear and continues to be researched. ==Effects on cell growth and differentiation == GDF11 belongs to the transforming growth factor beta superfamily that controls anterior-posterior patterning by regulating the expression of Hox genes. It determines Hox gene expression domains and rostrocaudal identity in the caudal spinal cord. During mouse development, GDF11 expression begins in the tail bud and caudal neural plate region. GDF knock-out mice display skeletal defects as a result of patterning problems with anterior-posterior positioning. In the mouse adult central nervous system, GDF11 alone can improve the cerebral vasculature and enhance neurogenesis.〔 This cytokine also inhibits the proliferation of olfactory receptor neuron progenitors to regulate the number of olfactory receptor neurons occurring in the olfactory epithelium, and controls the competence of progenitor cells to regulate numbers of retinal ganglionic cells developing in the retina. Other studies in mice suggest that GDF11 is involved in mesodermal formation and neurogenesis during embryonic development. The members of this TGF-β superfamily are involved in the regulation of cell growth and differentiation not only in embryonic tissues, but adult tissues as well.〔(【引用サイトリンク】url=http://www.genecards.org/cgi-bin/carddisp.pl?gene=GDF11 )〕 GDF11 can bind type I TGF-beta superfamily receptors ACVR1B (ALK4), TGFBR1 (ALK5) and ACVR1C (ALK7), but predominantly uses ALK4 and ALK5 for signal transduction.〔 GDF11 is closely related to myostatin, a negative regulator of muscle growth. Both myostatin and GDF11 are involved in the regulation of cardiomyocyte proliferation. GDF11 is also a negative regulator of neurogenesis,〔〔 the production of islet progenitor cells, the regulation of kidney organogenesis, pancreatic development, the rostro-caudal patterning in the development of spinal cords,〔 and is a negative regulator of chondrogenesis. Due to the similarities between myostatin and GDF11, the actions of GDF11 are likely regulated by WFIKKN2, a large extracellular multidomain protein consisting of follistatin, immunoglobulin, protease inhibitor, and NTR domains.〔(【引用サイトリンク】title=Both WFIKKN1 and WFIKKN2 Have High Affinity for Growth and Differentiation Factors 8 and 11 )〕 WFIKKN2 has a high affinity for GDF11, and previously has been found to inhibit the biological activities of myostatin.〔(【引用サイトリンク】url=http://www.genecards.org/cgi-bin/carddisp.pl?gene=WFIKKN2 )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「GDF11」の詳細全文を読む スポンサード リンク
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