Resonance assignments and solution structure of the second RNA-binding domain of sex-lethal determined by multidimensional heteronuclear magnetic resonance.
Resonance assignments and solution structure of the second RNA-binding domain of sex-lethal determined by multidimensional heteronuclear magnetic resonance.
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多维异核磁共振确定的性致死第二个RNA结合域的共振分配和溶液结构。
DOI：
10.1021/bi00250a031
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发表时间：
1994
期刊：
影响因子：
2.9
通讯作者：
Wemmer,DE
中科院分区：
文献类型：
--
作者：
Lee,AL;Kanaar,R;Rio,DC;Wemmer,DE
摘要：RNA结合蛋白性致死蛋白(SXL)是果蝇性别分化和剂量补偿的重要调节因子。这种调节活性是SXL与参与前mRNA剪接的富含尿苷的RNA链结合的能力的结果。SXL含有两个RNP共同型RNA结合域(RBD)。本文用多维异核核磁共振研究了含有第二RNA结合区(RBD-2)的部分SXL(氨基酸199-294)的结构。从~(15)N和~(13)C/~(15)N均一标记的蛋白质中获得了几乎完全的~1H、~(13)C和~(15)N共振归属。这些指认被用来分析3D15N分离的NOESY谱和13C/13C分离的4DNOESY谱，它们产生了494个总距离约束和169个长程NOE派生距离约束。与4l主干二面体限制一起，这些距离限制被用来产生一个中等分辨率的计算结构家族，它显示了在其他含有RBD的蛋白质中发现的/fa/3-fiafi三重折叠。残基11-93的主链原子对平均结构的RMSD为1.55±0.30 A，而参与二级结构的主链原子的RMSD为0.76±0.14 A。在第一螺旋的N-末端鉴定了一个封顶盒[Harper，E.T.，&Rose，G.D.(1993)BioChemical 32,7605-7609]，并用短程和中程NOES进行了表征。最后，讨论了SXL RBD-2与其他含有RBD的蛋白质在结构上的显著异同。果蝇二元开关基因SXL，1在体细胞和生殖系的性发育中起着核心的指导作用。它的表达模式是由上游事件启动的，涉及X：A比率的早期发育，取决于生物体的性状态
Revised Manuscript Received September 12, 1994® abstract: The RNA-binding proteinSex-lethal (Sxl) is a critical regulator of sexual differentiation and dosage compensation in Drosophila. This regulatory activity is a consequence of the ability of Sxl to bind uridine-rich RNA tracts involved in pre-mRNA splicing. Sxl containstwo RNP consensus-type RNA-binding domains (RBDs). A structural study of a portion of Sxl (amino acids 199—294) containing the second RNA-binding domain (RBD-2) using multidimensional heteronuclear NMR is presented here. Nearly complete'H, 13C, and 15N resonance assignments have been obtained from 15N-and 13C/15N-uniformly labeled protein. These assignments were used to analyze 3D 15N-separated NOESY and 13C/13C-separated 4D NOESY spectra which produced 494 total and 169 long-rangeNOE-derived distance restraints. Along with 4l backbone dihedral restraints, these distance restraints were employed to generate an intermediate-resolution familyof calculated stmctures, which exhibits the/fa/3—fiafi tertiary fold found in other RBD-containing proteins. The RMSD to the average structure for the backbone atoms of residues 11—93 is 1.55±0.30 A, while the RMSD for backbone atoms involved in secondary structure is 0.76±0.14 A. A capping box [Harper, E. T., & Rose, G. D.(1993) Biochemistry 32, 7605—7609] was identified at the N-terminus of the first helix and has been characterized by short-and medium-range NOEs. Finally, significant structural similarities and differences between Sxl RBD-2 and otherRBD-containing proteins are discussed.The Drosophila binary switch gene, Sex-lethal (Sxl), 1 plays a central role in directing events during somaticand germline sexual development. Its expression mode, initiated by upstream events involving the X: A ratio early indevelopment, is dependent upon the sexual state of the organism