Growth factor modulation of insulin-like growth factor-binding proteins in rat osteoblast-like cells.
Growth factor modulation of insulin-like growth factor-binding proteins in rat osteoblast-like cells.
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生长因子对大鼠成骨细胞样细胞中胰岛素样生长因子结合蛋白的调节。
DOI：
10.1210/endo.133.3.7689954
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发表时间：
1993
期刊：
影响因子：
4.8
通讯作者：
Y.
中科院分区：
文献类型：
--
作者：
T. Chen;L. Chang;D. DiGregorio;A. Perlman;Y.
胰岛素样生长因子（IGFs）刺激培养的成骨细胞的生长和分化，这些生物学功能可以通过其结合蛋白（IGFBPs）进行调节。先前的研究表明，IGFBP-2是由胎鼠成骨样细胞（ROB）合成的主要IGFBP，其也分泌少量24千道尔顿IGFBP，推测为IGFBP-4。在这项研究中，我们研究了各种生长因子对IGFBPs丰度的调节。通过免疫沉淀和配体印迹，我们已经证明，在本研究中出现的25千道尔顿的24千道尔顿蛋白是IGFBP-4，其水平被碱性成纤维细胞生长因子（bFGF）和血小板衍生生长因子BB同源二聚体强烈增强。在1 nM时检测到这些因子对IGFBP-4的诱导（10- 30倍），在10 nM时增加至对照的50- 70倍。IGFBP-4的丰度也增加，但程度较低的转化生长因子-α（TGF-α）和表皮生长因子（EGF）。与其他生长因子的作用相反，TGF-β 1显著降低IGFBP-2和IGFBP-4的水平。PTH和PTH相关肽不诱导ROB细胞IGFBPs。这与恶性大鼠成骨细胞样细胞系UMR 106-01的发现相反。由于bFGF治疗后的IGFBP-4的水平仍然升高，在存在的羟基脲，诱导可能是独立的刺激作用，这些因素对有丝分裂。为了进一步研究IGFBPs被调节的机制，用放线菌素D和放线菌酮与和不与bFGF处理培养物。放线菌素D抑制IGFBP-2和IGFBP-4的合成，但不抑制IGFBP-2的合成。从ROB细胞中提取的总RNA与IGFBP-2和IGFBP-4的特异性大鼠互补DNA杂交，分别显示1.3和2.2个酶的单转录本。无论蛋白质水平的变化如何，在bFGF处理后2、8和24小时，IGFBP-4转录物的丰度与溶剂处理的对照组没有差异。同样，IGFBP-2和IGFBP-4的信使RNA水平在TGF-β 1治疗的相同时间过程中没有变化。这些数据表明，在ROB细胞中，IGFBPs的丰度受到各种生长因子的差异调节。（400字处截断摘要）
Insulin-like growth factors (IGFs) stimulate growth and differentiation of osteoblasts in culture, and these biological functions can be modulated by their binding proteins (IGFBPs). Previous studies have shown that IGFBP-2 is the major IGFBP synthesized by fetal rat osteoblast-like (ROB) cells, which also secret a minor 24-kilodalton IGFBP, presumably IGFBP-4. In this study we examined the modulation of the abundance of IGFBPs by various growth factors. By immunoprecipitation and ligand blotting, we have proved that the 24 kilodalton protein, which appeared at 25 kilodalton in the present study, is IGFBP-4, whose level was strongly enhanced by basic fibroblast growth factor (bFGF) and platelet-derived growth factor BB homodimer. Induction of IGFBP-4 by these factors was detected at 1 nM (10- to 30-fold) and increased to 50- to 70-fold of control at 10 nM. The abundance of IGFBP-4 was also increased but to a lesser degree by transforming growth factor-alpha (TGF-alpha) and epidermal growth factor (EGF). As opposed to the actions of other growth factors, TGF-beta 1 substantially lowered the levels of IGFBP-2 and IGFBP-4. PTH and PTH-related peptide did not induce IGFBPs in ROB cells. This is in contrast to the findings from a malignant rat osteoblast-like cell line, UMR 106-01. Since the level of IGFBP-4 after bFGF treatment remained elevated in the presence of hydroxyurea, the induction was likely to be independent of the stimulatory effects of these factors on mitogenesis. To further examine the mechanisms by which IGFBPs were regulated, cultures were treated with actinomycin D and cycloheximide with and without bFGF. Although the synthesis of IGFBP-2 and IGFBP-4 were both inhibited by cycloheximide, actinomycin D blocked the synthesis of basal and bFGF-induced IGFBP-4 but not IGFBP-2. Total RNA extracted from ROB cells and hybridized with specific rat complementary DNAs for IGFBP-2 and IGFBP-4 showed single transcripts of 1.3 and 2.2 kilobases, respectively. Regardless of the changes at the protein level, the abundance of IGFBP-4 transcripts was not different from the vehicle-treated controls at 2, 8, and 24 h after bFGF treatment. Similarly, the levels of messenger RNA for IGFBP-2 and IGFBP-4 did not change during the same time course in the TGF-beta 1 treatment. These data demonstrate that in ROB cells, the abundance of IGFBPs is differentially regulated by various growth factors.(ABSTRACT TRUNCATED AT 400 WORDS)
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DOI：
10.1073/pnas.88.17.7481
发表时间：
1991-09-01
影响因子：
11.1
作者：
JONES, JI;DERCOLE, AJ;CLEMMONS, DR
通讯作者：
CLEMMONS, DR
羊水来源的胰岛素样生长因子结合蛋白的纯化制剂含有具有生物活性的多聚体形式。
影响因子：
4.8
作者：
Busby,WH;Hossenlopp,P;Binoux,M;Clemmons,DR
通讯作者：
Clemmons,DR
影响因子：
4.8
作者：
MCCARTHY, TL;CENTRELLA, M;CANALIS, E
通讯作者：
CANALIS, E
影响因子：
4.8
作者：
MCCARTHY, TL;CENTRELLA, M;CANALIS, E
通讯作者：
CANALIS, E
影响因子：
4.8
作者：
MCCARTHY, TL;CENTRELLA, M;CANALIS, E
通讯作者：
CANALIS, E