{"title":"DEAD-box解旋酶DDX3X解旋RNA双链机制的揭示:对原蛋白协同作用和作用的见解","authors":"Sudhaker Dharavath , He Song , Xinhua Ji","doi":"10.1016/j.bbrc.2025.152206","DOIUrl":null,"url":null,"abstract":"<div><div>DDX3X, a human DEAD-box helicase involved in ATP-dependent unwinding of short RNA duplexes, plays a pivotal role in RNA metabolism, cancer progression, and HIV-1 infection. It is composed of an N-terminal region (N: residues 1–131), a helicase core containing two RecA-like domains (D1D2: residues 132–607), and a C-terminal tail (C: residues 608–662). Previous research has shown that D1D2 forms a pre-unwound complex with dsRNA, exhibiting two-molecule cooperativity for both RNA-unwinding and ATPase activities. However, the cooperative mechanism by which the full-length DDX3X (N-D1D2-C) unwinds RNA remains to be fully understood. Knowing that the C-terminal tail is crucial for oligomerization, we have created an N-truncated form of DDX3X (D1D2-C: residues 132–662) for further investigation. Our findings indicate that D1D2-C oligomerizes in the presence of RNA substrate, exhibits three-molecule cooperativity for RNA-unwinding activity, and displays two-molecule cooperativity for ATPase activity. Furthermore, D1 residue E186 and C-terminal tail are essential for the oligomerization of D1D2-C, enabling two types of subunit interface to form, one between two D1 domains (C-D2D1:D1D2-C) and the other between two C-terminal tails (D1D2-C:C-D2D1). These results offer new insights into the molecular mechanism of cooperative RNA unwinding by DDX3X.</div></div>","PeriodicalId":8779,"journal":{"name":"Biochemical and biophysical research communications","volume":"777 ","pages":"Article 152206"},"PeriodicalIF":2.5000,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Unraveling the mechanism of RNA duplex unwinding by DEAD-box helicase DDX3X: Insights into Cooperativity and roles of protomers\",\"authors\":\"Sudhaker Dharavath , He Song , Xinhua Ji\",\"doi\":\"10.1016/j.bbrc.2025.152206\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>DDX3X, a human DEAD-box helicase involved in ATP-dependent unwinding of short RNA duplexes, plays a pivotal role in RNA metabolism, cancer progression, and HIV-1 infection. It is composed of an N-terminal region (N: residues 1–131), a helicase core containing two RecA-like domains (D1D2: residues 132–607), and a C-terminal tail (C: residues 608–662). Previous research has shown that D1D2 forms a pre-unwound complex with dsRNA, exhibiting two-molecule cooperativity for both RNA-unwinding and ATPase activities. However, the cooperative mechanism by which the full-length DDX3X (N-D1D2-C) unwinds RNA remains to be fully understood. Knowing that the C-terminal tail is crucial for oligomerization, we have created an N-truncated form of DDX3X (D1D2-C: residues 132–662) for further investigation. Our findings indicate that D1D2-C oligomerizes in the presence of RNA substrate, exhibits three-molecule cooperativity for RNA-unwinding activity, and displays two-molecule cooperativity for ATPase activity. Furthermore, D1 residue E186 and C-terminal tail are essential for the oligomerization of D1D2-C, enabling two types of subunit interface to form, one between two D1 domains (C-D2D1:D1D2-C) and the other between two C-terminal tails (D1D2-C:C-D2D1). These results offer new insights into the molecular mechanism of cooperative RNA unwinding by DDX3X.</div></div>\",\"PeriodicalId\":8779,\"journal\":{\"name\":\"Biochemical and biophysical research communications\",\"volume\":\"777 \",\"pages\":\"Article 152206\"},\"PeriodicalIF\":2.5000,\"publicationDate\":\"2025-06-13\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Biochemical and biophysical research communications\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0006291X25009210\",\"RegionNum\":3,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"BIOCHEMISTRY & MOLECULAR BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biochemical and biophysical research communications","FirstCategoryId":"99","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0006291X25009210","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
Unraveling the mechanism of RNA duplex unwinding by DEAD-box helicase DDX3X: Insights into Cooperativity and roles of protomers
DDX3X, a human DEAD-box helicase involved in ATP-dependent unwinding of short RNA duplexes, plays a pivotal role in RNA metabolism, cancer progression, and HIV-1 infection. It is composed of an N-terminal region (N: residues 1–131), a helicase core containing two RecA-like domains (D1D2: residues 132–607), and a C-terminal tail (C: residues 608–662). Previous research has shown that D1D2 forms a pre-unwound complex with dsRNA, exhibiting two-molecule cooperativity for both RNA-unwinding and ATPase activities. However, the cooperative mechanism by which the full-length DDX3X (N-D1D2-C) unwinds RNA remains to be fully understood. Knowing that the C-terminal tail is crucial for oligomerization, we have created an N-truncated form of DDX3X (D1D2-C: residues 132–662) for further investigation. Our findings indicate that D1D2-C oligomerizes in the presence of RNA substrate, exhibits three-molecule cooperativity for RNA-unwinding activity, and displays two-molecule cooperativity for ATPase activity. Furthermore, D1 residue E186 and C-terminal tail are essential for the oligomerization of D1D2-C, enabling two types of subunit interface to form, one between two D1 domains (C-D2D1:D1D2-C) and the other between two C-terminal tails (D1D2-C:C-D2D1). These results offer new insights into the molecular mechanism of cooperative RNA unwinding by DDX3X.
期刊介绍:
Biochemical and Biophysical Research Communications is the premier international journal devoted to the very rapid dissemination of timely and significant experimental results in diverse fields of biological research. The development of the "Breakthroughs and Views" section brings the minireview format to the journal, and issues often contain collections of special interest manuscripts. BBRC is published weekly (52 issues/year).Research Areas now include: Biochemistry; biophysics; cell biology; developmental biology; immunology
; molecular biology; neurobiology; plant biology and proteomics