Department of Biochemistry and Structural Biology, and Greehey Children's Cancer Research Institute, The University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Dr., San Antonio, TX, 78229, USA.
Biomol NMR Assign. 2021 Oct;15(2):461-466. doi: 10.1007/s12104-021-10046-3. Epub 2021 Aug 26.
SERBP1 is a multifunctional mRNA-binding protein that has been shown to play a regulatory role in a number of biological processes such as thrombosis, DNA damage repair, and the cellular response to nutrient deprivation. Additionally, SERBP1 is upregulated in glioblastoma, leukemia as well as liver, prostrate and ovarian cancers where it has been implicated in metastatic disease and poor patient outcomes. SERBP1 binds target mRNA, stabilizing and regulating the post-translational expression of the transcript. Since SERBP1 lacks canonical RNA-binding motifs such as RRM domains or zinc fingers, its target recognition and binding mechanisms are not well understood. Recent reports suggest that it is capable of recognizing both RNA sequence motifs and structured domains. Here we report the production and purification of the intrinsically disordered C-terminal domain of SERBP1, the assignment of the H, C, N backbone resonances of the protein by solution-state NMR, and secondary structure predictions. We show that the protein is not entirely disordered and identify an α-helix that was stable under the experimental conditions. This work is the first step toward understanding the structural basis underpinning the molecular mechanisms of SERBP1 functions, particularly interactions with mRNA targets.
SERBP1 是一种多功能的 mRNA 结合蛋白,已被证明在许多生物学过程中发挥调节作用,如血栓形成、DNA 损伤修复和细胞对营养缺乏的反应。此外,SERBP1 在神经胶质瘤、白血病以及肝癌、前列腺癌和卵巢癌中上调,其与转移疾病和患者预后不良有关。SERBP1 结合靶 mRNA,稳定和调节转录本的翻译后表达。由于 SERBP1 缺乏经典的 RNA 结合基序,如 RRM 结构域或锌指,其靶识别和结合机制尚不清楚。最近的报告表明,它能够识别 RNA 序列基序和结构域。在这里,我们报告了 SERBP1 无规卷曲 C 末端结构域的表达和纯化,通过溶液 NMR 对该蛋白的 H、C、N 骨架共振进行了归属,并预测了二级结构。我们表明该蛋白并非完全无规卷曲,并鉴定出一个在实验条件下稳定的α-螺旋。这项工作是理解 SERBP1 功能分子机制的结构基础,特别是与 mRNA 靶标相互作用的第一步。