Role of IGF binding protein-3 (IGFBP-3) and IGFBP-5 as modulators of nuclear hormone signalling

胰岛素样生长因子是参与大多数组织生长的小蛋白质。它们的作用是通过与血液和细胞外较大的蛋白质（称为igfbp）结合来调节的。然而，在细胞内也发现了一些igfbp，它们似乎在细胞内执行其他功能。我们认为，其中两种结合蛋白，IGFBP-3和IGFBP-5，改变了细胞对维生素A和维生素d的反应方式。这两种维生素在细胞生长和某些细胞执行特定功能的方式中很重要。在试管实验中，IGFBP-3和IGFBP-5直接与调节这些激素作用的受体相互作用。如果同样的事情发生在细胞内，IGFBP-3和IGFBP-5可能会改变这些受体对细胞外信号的反应方式。我们将研究这些igfbp对活细胞和整个动物的影响，以及这与人类疾病的关系。如果我们能够了解IGFBP-3和IGFBP-5如何影响细胞对维生素A和D的反应，那么我们可能能够开发出治疗某些人类疾病的新方法。

The insulin-like growth factors are small proteins involved in the growth of most tissues. Their actions are regulated by binding to larger proteins (known as IGFBPs) in the bloodstream and outside the cell. However, some IGFBPs are also found inside cells, where they seem to carry out other functions. We believe that two of these binding proteins, IGFBP-3 and IGFBP-5, change the way cells respond to vitamin A and vitamin D. These two vitamins are important in cell growth and in the way certain cells perform specialised functions. In test-tube experiments, IGFBP-3 and IGFBP-5 interact directly with the receptors that regulate the effects of these hormones. If the same thing happens inside the cell, IGFBP-3 and IGFBP-5 could change the way these receptors respond to signals from outside the cell. We will investigate what effect these IGFBPs have in living cells and in whole animals and how this may relate to human disease. If we are able to understand how IGFBP-3 and IGFBP-5 affect the way cells respond to vitamin A and D, then we may be able to develop new ways to treat certain human diseases.