NCI X-ray free electron laser (XFEL) initiative

目前，有两项实验正在进行中。1）。研究时间分辨的 使用XFEL的核糖开关中的配体触发的构象变化。梁时间被授予基于 我们在2019年的竞争性提案中，就在大流行关闭之前。2）。纳微米 在国际空间站上的微重力环境下结晶 (ISS)与NASA合作。我们的样品已经在国际空间站上。我们 等待下一个宇航员可以在国际空间站上进行实验的窗口时间 并且样本返回地面以便在LCLS立即收集数据。过去 五年来，安排这项实验已被证明是极具挑战性的，因为 样品返回时间表高度不确定性和获得XFEL的极大困难 以满足样品返回时间表。这一问题进一步恶化， 与去年疫情相关的停工。无论如何，我们将继续努力， 实验最终成功完成。鉴于这一流行病 我已经对我们的计划做了一个认真的和战略性的改变。相反 仅仅依靠XFEL，我们无法控制的资源， 易受干扰，我们被迫采用不同的技术来执行， 实现我们探索RNA结构动力学和构象的研究目标 空间

Currently, two experiments are pending. 1). Investigating time-resolved process of ligand-triggered conformation change in riboswitch using XFEL. The beam time was awarded based on our competitive proposal in 2019, right before the pandemic shutdown. 2). nano-micron crystallization under the microgravity environment onboard of the International Space Station (ISS) under the collaboration with NASA. Our samples are already on board of ISS. We're waiting for the next window time where an astronaut can perform the experiment onboard of ISS and the samples are returned ground for the immediate data collection at LCLS. For the past five years, arranging this experiment has been proven to be extremely challenging because of high degree of uncertainty in sample return schedules and great difficulty in securing a XFEL beamtime to meet the sample returning schedule. The problem was exacerbated further by the pandemic related shutdown in the last year. Regardless, we will continue our effort till the experiment is eventually performed and completed successfully. In light of the pandemic related interruption, I have made a conscientious and strategic change in our program. Instead of solely relying on the XFEL, the resource that we have no control over and is highly susceptible to interruption, we were forced to adopt different technologies to carry out and fulfill our research goal of exploring RNA structural dynamics and conformational space.