State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Innovation Center for Cell Signaling Network, Xiamen University, Xiamen, 361102, China.
Department of Physics, Xiamen University, Xiamen, 361005, China.
Protein Cell. 2021 Nov;12(11):858-876. doi: 10.1007/s13238-020-00810-x. Epub 2021 Jan 2.
There remains a significant gap in our quantitative understanding of crosstalk between apoptosis and necroptosis pathways. By employing the SWATH-MS technique, we quantified absolute amounts of up to thousands of proteins in dynamic assembling/de-assembling of TNF signaling complexes. Combining SWATH-MS-based network modeling and experimental validation, we found that when RIP1 level is below 1000 molecules/cell (mpc), the cell solely undergoes TRADD-dependent apoptosis. When RIP1 is above ~1000 mpc, pro-caspase-8 and RIP3 are recruited to necrosome respectively with linear and nonlinear dependence on RIP1 amount, which well explains the co-occurrence of apoptosis and necroptosis and the paradoxical observations that RIP1 is required for necroptosis but its increase down-regulates necroptosis. Higher amount of RIP1 (>46,000 mpc) suppresses apoptosis, leading to necroptosis alone. The relation between RIP1 level and occurrence of necroptosis or total cell death is biphasic. Our study provides a resource for encoding the complexity of TNF signaling and a quantitative picture how distinct dynamic interplay among proteins function as basis sets in signaling complexes, enabling RIP1 to play diverse roles in governing cell fate decisions.
我们对细胞凋亡和坏死性凋亡途径之间的串扰的定量理解仍然存在很大差距。通过采用 SWATH-MS 技术，我们在 TNF 信号转导复合物的动态组装/解组装过程中定量了多达数千种蛋白质的绝对数量。结合基于 SWATH-MS 的网络建模和实验验证，我们发现当 RIP1 水平低于约 1000 个分子/细胞（mpc）时，细胞仅经历依赖 TRADD 的细胞凋亡。当 RIP1 高于约 1000 mpc 时，分别有前胱天蛋白酶-8 和 RIP3 被募集到坏死小体，与 RIP1 数量呈线性和非线性依赖关系，这很好地解释了细胞凋亡和坏死性凋亡的同时发生以及 RIP1 对于坏死性凋亡是必需的但它的增加会下调坏死性凋亡的矛盾观察。更高水平的 RIP1（>~46,000 mpc）抑制细胞凋亡，导致仅发生坏死性凋亡。RIP1 水平与坏死性凋亡或总细胞死亡的发生之间的关系呈双相性。我们的研究为 TNF 信号的复杂性提供了一种编码，并为不同蛋白质之间的动态相互作用如何作为信号复合物中的基组发挥作用提供了一个定量图像，使 RIP1 能够在调节细胞命运决策中发挥多种作用。
