Chany-Fournier F, Jiang P H, Chany C
Institut National de la Santé et de la Recherche Médicale, Hôpital Saint Vincent de Paul, Paris, France.
J Cell Physiol. 1990 Oct;145(1):173-80. doi: 10.1002/jcp.1041450123.
Sarcolectin is an endolectin present in a great variety of conjunctival tissues (muscles, cartilage, sarcomas), but also in brain or placental extracts of vertebrates, including primates. When purified to electrophoretical homogeneity as a 65-kd protein, it agglutinates cells and has an affinity for simple sugars. In addition, it is able to inhibit the synthesis of interferon (IFN)-dependent secondary proteins and to restore cells to their status ad primum. The biological effect of Poly(I).Poly(C)-induced feedback interferon is inhibited by the addition of sarcolectins, which also abolishes cellular refractoriness to repeated IFN induction. Similarly, sequential association of, first, Poly(I).Poly(C); 4-5 h later, sarcolectin restores the full capacity of both to promote cell growth, unrestrained by IFN. Indeed, the secondary proteins which are in the process of being synthesized are inhibited. In a great variety of animal cells, sarcolectin can also initiate growth after it has been blocked by IFN. This is not an all-or-none effect, but a balance may be struck by IFN and sarcolectin, depending on their respective concentrations and specific activity. We propose that the coordination of these cellular functions of Poly(I).Poly(C), IFN, and sarcolectin takes place in the form of a triangular growth-regulatory cycle and postulate that they thus maintain a balance during differentiated normal tissue development.
肌集蛋白是一种内凝集素，存在于多种结膜组织（肌肉、软骨、肉瘤）中，也存在于包括灵长类动物在内的脊椎动物的脑或胎盘提取物中。当纯化至电泳纯的65kd蛋白时，它能凝集细胞并对单糖具有亲和力。此外，它能够抑制干扰素（IFN）依赖性二级蛋白的合成，并使细胞恢复到初始状态。添加肌集蛋白可抑制聚肌苷酸-聚胞苷酸（Poly(I).Poly(C)）诱导的反馈干扰素的生物学效应，这也消除了细胞对重复IFN诱导的不应性。同样，首先加入Poly(I).Poly(C)；4-5小时后加入肌集蛋白，二者依次作用可恢复促进细胞生长的全部能力，且不受IFN的限制。实际上正在合成的二级蛋白受到了抑制。在多种动物细胞中，肌集蛋白在被IFN阻断后也能启动生长。这不是一种全或无的效应，而是IFN和肌集蛋白之间可能会达到一种平衡，这取决于它们各自的浓度和比活性。我们提出，Poly(I).Poly(C)、IFN和肌集蛋白的这些细胞功能的协调是以三角生长调节循环的形式发生的，并推测它们在分化的正常组织发育过程中因此保持平衡。
