Shafiq Arooj, Campbell Louise J, Owen Darerca, Mott Helen R
Department of Biochemistry, 80, Tennis Court Road, Cambridge, CB2 1GA, UK.
Barrett Hodgson University, Korangi Creek, Salim Habib Campus, NC-24, Deh Dih, Korangi Creek, Karachi, 74900, Sindh, Pakistan.
Biomol NMR Assign. 2020 Apr;14(1):87-91. doi: 10.1007/s12104-019-09925-7. Epub 2020 Jan 8.
The Ral proteins (RalA and RalB) are small G proteins of the Ras family that have been implicated in exocytosis, endocytosis, transcriptional regulation and mitochondrial fission, as well as having a role in tumourigenesis. RalA and RalB are activated downstream of the master regulator, Ras, which causes the nucleotide exchange of GDP for GTP. Here we report the H, N and C resonance assignments of RalA in its active form bound to the GTP analogue GMPPNP. We also report the backbone assignments of RalA in its inactive, GDP-bound form. The assignments give insight into the switch regions, which change conformation upon nucleotide exchange. These switch regions are invisible in the spectra of the active, GMPPNP bound form but the residues proximal to the switches can be monitored. RalA is also an important drug target due to its over activation in some cancers and these assignments will be extremely useful for NMR-based screening approaches.
Ral蛋白（RalA和RalB）是Ras家族的小G蛋白，参与胞吐作用、胞吞作用、转录调控和线粒体分裂，在肿瘤发生中也发挥作用。RalA和RalB在主调节因子Ras的下游被激活，Ras会导致GDP与GTP进行核苷酸交换。在此，我们报告了与GTP类似物GMPPNP结合的活性形式的RalA的氢、氮和碳共振归属。我们还报告了非活性的、结合GDP形式的RalA的主链归属。这些归属有助于了解开关区域，开关区域在核苷酸交换时会改变构象。这些开关区域在结合活性GMPPNP形式的光谱中不可见，但可以监测开关附近的残基。由于RalA在某些癌症中过度激活，它也是一个重要的药物靶点，这些归属对于基于核磁共振的筛选方法将极为有用。
