Structure and position-specific interactions of prion-like domains in transcription factor Efg1 phase separation.
Structure and position-specific interactions of prion-like domains in transcription factor Efg1 phase separation.
复制标题
转录因子 Efg1 相分离中朊病毒样结构域的结构和位置特异性相互作用。
DOI：
10.1101/2023.11.09.566450
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Fawzi,NicolasL
中科院分区：
文献类型：
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作者：
Wang,Szu-Huan;Zheng,Tongyin;Fawzi,NicolasL
白色念珠菌是人类微生物群中的重要成员，它可以在白细胞态和不透明细胞态之间进行表观遗传转换，从而实现从共生到致病的机会性转换。这种转录开关受到一组转录因子(TF)的精确调控，其中增强型丝状生长蛋白1(Efg1)起着核心作用。以前的研究已经强调了Efg1的S蛋白酪蛋白样域(PrLD)的重要性，以及该蛋白在白念珠菌从白色到不透明转变过程中经历相分离的能力。然而，Efg1相分离的潜在分子机制仍未得到充分研究。在本研究中，我们深入研究了Efg1相分离的生物物理基础，揭示了N端(N)和C端(C)PrLD的显著贡献。通过核磁共振结构分析，我们发现Efg1、N-PrLD和C-PrLD大部分是无序的，但在两个结构域中都有明显的部分α-螺旋二级结构。核磁共振滴定实验表明，N-PrLD中的部分螺旋结构既是Efg1与RNA相互作用的中心，也是自我相互作用的中心。利用缩合相核磁共振波谱，我们揭示了Efg1相分离背后的各种氨基酸相互作用。特别是，我们强调了酪氨酸残基在PrLD的瞬时α-螺旋结构中的不可或缺的作用，特别是在N-PrLD中，与C-PrLD相比，它在稳定相分离方面发挥了不可或缺的作用。我们的研究提供了α-螺旋结构处于相分离状态的证据，并强调了这些结构中芳香族残基对相分离的特殊重要性。综上所述，这些结果增强了对Fc。白化转录因子相互作用的理解，这些相互作用导致毒力，并为针对转录开关的潜在抗真菌治疗提供了重要的基础。
Candida albicans, a prominent member of the human microbiome, can make an opportunistic switch from commensal coexistence to pathogenicity accompanied by an epigenetic shift between the white and opaque cell states. This transcriptional switch is under precise regulation by a set of transcription factors (TFs), with Enhanced Filamentous Growth Protein 1 (Efg1) playing a central role. Previous research has emphasized the importance of Efg1's prion-like domain (PrLD) and the protein's ability to undergo phase separation for the white-to-opaque transition ofC. albicans. However, the underlying molecular mechanisms of Efg1 phase separation have remained underexplored. In this study, we delved into the biophysical basis of Efg1 phase separation, revealing the significant contribution of both N-terminal (N) and C-terminal (C) PrLDs. Through NMR structural analysis, we found that Efg1 N-PrLD and C-PrLD are mostly disordered but have prominent partialα-helical secondary structures in both domains. NMR titration experiments suggest that the partially helical structures in N-PrLD act as hubs for self-interaction as well as Efg1 interaction with RNA. Using condensed-phase NMR spectroscopy, we uncovered diverse amino acid interactions underlying Efg1 phase separation. Particularly, we highlight the indispensable role of tyrosine residues within the transientα-helical structures of PrLDs particularly in the N-PrLD compared to the C-PrLD in stabilizing phase separation. Our study provides evidence that the transientα-helical structure is present in the phase-separated state and highlights the particular importance of aromatic residues within these structures for phase separation. Together, these results enhance the understanding ofC. albicanstranscription factor interactions that lead to virulence and provide a crucial foundation for potential antifungal therapies targeting the transcriptional switch.