The continuous nature of timing reprogramming in an interceptive task

The time course of movement timing reprogramming was examined in a task requiring temporal coincidence of the conclusion of a forehand drive with the arrival of a moving luminous target at the end of an electronic trackway. The moving target departed from one end of the trackway at a constant velocity of 2?m ^. s^?1, and for a part of the trials its velocity was increased to 3?m ^. s^?1. Target velocity was modified at different moments during stimulus displacement, producing times-to-arrival after velocity increment (TAVIs) from 100 to 600?ms. The effect of specific practice on movement reprogramming was also examined. The results showed early adjustments to the action (TAVIs = 100?–?200?ms) that seemed to be stereotyped, while feedback-based corrections were implemented only at TAVIs of 300?ms or longer. Temporal accuracy was progressively increased as longer TAVIs were provided up to 600?ms. Skill training led to an overall increment of temporal accuracy, but no effect of specific practice was found. The results indicate that timing reprogramming in interceptive actions is a continuous process limited mainly by intrinsic factors: latency to initiate more effective adjustments to the action, and rate-of-movement timing reprogramming.     

Integrated metabolism and epigenetic modifications in the macrophages of mice in responses to cold stress

The negative effects of low temperature can readily induce a variety of diseases. We sought to understand the reasons why cold stress induces disease by studying the mechanisms of fine-tuning in macrophages following cold exposure. We found that cold stress triggers increased macrophage activation accompanied by metabolic reprogramming of aerobic glycolysis. The discovery, by genome-wide RNA sequencing, of defective mitochondria in mice macrophages following cold exposure indicated that mitochondrial defects may contribute to this process. In addition, changes in metabolism drive the differentiation of macrophages by affecting histone modifications. Finally, we showed that histone acetylation and lactylation are modulators of macrophage differentiation following cold exposure. Collectively, metabolism-related epigenetic modifications are essential for the differentiation of macrophages in cold-stressed mice, and the regulation of metabolism may be crucial for alleviating the harm induced by cold stress.     

表观遗传修饰和代谢重编程对乳腺癌干细胞的调控

概乳腺癌已居我国女性恶性肿瘤死亡率首位。近来研究表明,乳腺肿瘤组织内有少量具有自我更新和分化潜能的肿瘤干细胞,这些肿瘤干细胞在乳腺癌发生、发展、转移及复发过程中起关键作用。深入研究乳腺癌干细胞的调控机制对乳腺癌的预防和治疗具有十分重要意义。本文综合近期的研究成果,概括了表观遗传修饰和代谢重编程对上皮间质转化及乳腺癌干细胞的调控机制,且系统地分析与总结了表观遗传修饰、代谢重编程、上皮间质转化和乳腺癌干细胞之间的相互关系。     

人工基因线路的研究进展和未来挑战

基因线路是生命体对自身生命过程控制的动态调控系统。在工程化的设计原理的指导下,人工基因线路是对天然基因调控线路进行简单化处理和重新编程,以及引入自然界不存在的人造法则。人工基因线路由遗传开关、生物振荡器、逻辑门等组成,以执行诸多调控功能。多种多样的人工基因线路设计与构建,不仅极大地促进了人们对生命调控基本规律的认识,也进一步丰富了人们对天然的生物系统进行改造、再创的手段,并为医药健康、农业环境和工业发酵等领域的实际需求提供了全新解决方案。虽然在过去20年里,人们在人工基因线路领域取得了丰硕的研究成果,但是细胞体内蕴含着的众多复杂生化反应和信号传导途径,为设计和组装具有更加高级功能的基因线路带来了挑战。相应地,如何实现微小细胞内复杂基因线路的可预测设计组装,如何保障基因线路在复杂的体内外环境下发挥稳健的功能,将成为未来几年人工基因线路研究的关键核心问题和势必克服的重大挑战。