Reconstitution of the signal recognition particle of the halophilic archaeon Haloferax volcanii.
Reconstitution of the signal recognition particle of the halophilic archaeon Haloferax volcanii.
复制标题
嗜盐古菌 Haloferax volcanii 信号识别粒子的重建。
DOI：
10.1093/nar/gkf548
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发表时间：
2002
影响因子：
14.9
通讯作者：
Eichler,Jerry
中科院分区：
文献类型：
--
作者：
Tozik,Irit;Huang,Qiaojia;Zwieb,Christian;Eichler,Jerry
The signal recognition particle (SRP) is a ribonucleoprotein complex involved in the recognition and targeting of nascent extracytoplasmic proteins in all three domains of life. In Archaea, SRP contains 7S RNA like its eukaryal counterpart, yet only includes two of the six protein subunits found in the eukaryal complex. To further our understanding of the archaeal SRP, 7S RNA, SRP19 and SRP54 of the halophilic archaeonHaloferax volcaniihave been expressed and purified, and used to reconstitute the ternary SRP complex. The availability of SRP components from a haloarchaeon offers insight into the structure, assembly and function of this ribonucleoprotein complex at saturating salt conditions. While the amino acid sequences ofH.volcaniiSRP19 and SRP54 are modified presumably as an adaptation to their saline surroundings, the interactions between these halophilic SRP components and SRP RNA appear conserved, with the possibility of a few exceptions. Indeed, theH.volcaniiSRP can assemble in the absence of high salt. As reported with other archaeal SRPs, the limited binding ofH.volcaniiSRP54 to SRP RNA is enhanced in the presence of SRP19. Finally, immunolocalization reveals thatH.volcaniiSRP54 is found in the cytosolic fraction, where it is associated with the ribosomal fraction of the cell.
