Joint Center for Biosciences at Lee Gil Ya Cancer and Diabetes Institute, Gachon University for Medicine and Science, Incheon, Korea.
PLoS One. 2011;6(11):e26402. doi: 10.1371/journal.pone.0026402. Epub 2011 Nov 4.
Transforming Growth Factor--beta (TGFβ) superfamily ligands, including Activins, Growth and Differentiation Factors (GDFs), and Bone Morphogenetic Proteins (BMPs), are excellent targets for protein-based therapeutics because of their pervasiveness in numerous developmental and cellular processes. We developed a strategy termed RASCH (Random Assembly of Segmental Chimera and Heteromer), to engineer chemically-refoldable TGFβ superfamily ligands with unique signaling properties. One of these engineered ligands, AB208, created from Activin-βA and BMP-2 sequences, exhibits the refolding characteristics of BMP-2 while possessing Activin-like signaling attributes. Further, we find several additional ligands, AB204, AB211, and AB215, which initiate the intracellular Smad1-mediated signaling pathways more strongly than BMP-2 but show no sensitivity to the natural BMP antagonist Noggin unlike natural BMP-2. In another design, incorporation of a short N-terminal segment from BMP-2 was sufficient to enable chemical refolding of BMP-9, without which was never produced nor refolded. Our studies show that the RASCH strategy enables us to expand the functional repertoire of TGFβ superfamily ligands through development of novel chimeric TGFβ ligands with diverse biological and clinical values.
转化生长因子-β（TGFβ）超家族配体，包括激活素、生长分化因子（GDFs）和骨形态发生蛋白（BMPs），由于它们在众多发育和细胞过程中的普遍性，是蛋白质治疗的极佳靶点。我们开发了一种称为 RASCH（分段嵌合体和杂合体的随机组装）的策略，用于设计具有独特信号特性的化学可重折叠的 TGFβ 超家族配体。这些工程配体之一，AB208，由 Activin-βA 和 BMP-2 序列组成，表现出 BMP-2 的重折叠特征，同时具有激活素样信号属性。此外，我们发现了其他几种配体，AB204、AB211 和 AB215，它们比 BMP-2 更强烈地启动细胞内 Smad1 介导的信号通路，但与天然 BMP 拮抗剂 Noggin 不同，它们不像天然 BMP-2 那样敏感。在另一个设计中，BMP-2 的短 N 端片段的掺入足以使 BMP-9 进行化学重折叠，否则 BMP-9 既不能产生也不能重折叠。我们的研究表明，RASCH 策略使我们能够通过开发具有不同生物学和临床价值的新型嵌合 TGFβ 配体来扩展 TGFβ 超家族配体的功能范围。
