Kressler D, de la Cruz J, Rojo M, Linder P
Département de Biochimie Médicale, Centre Médical Universitaire, Université de Genève, Geneva, Switzerland.
Mol Cell Biol. 1998 Apr;18(4):1855-65. doi: 10.1128/MCB.18.4.1855.
A previously uncharacterized Saccharomyces cerevisiae open reading frame, YNR038W, was analyzed in the context of the European Functional Analysis Network. YNR038W encodes a putative ATP-dependent RNA helicase of the DEAD-box protein family and was therefore named DBP6 (DEAD-box protein 6). Dbp6p is essential for cell viability. In vivo depletion of Dbp6p results in a deficit in 60S ribosomal subunits and the appearance of half-mer polysomes. Pulse-chase labeling of pre-rRNA and steady-state analysis of pre-rRNA and mature rRNA by Northern hybridization and primer extension show that Dbp6p depletion leads to decreased production of the 27S and 7S precursors, resulting in a depletion of the mature 25S and 5.8S rRNAs. Furthermore, hemagglutinin epitope-tagged Dbp6p is detected exclusively within the nucleolus. We propose that Dbp6p is required for the proper assembly of preribosomal particles during the biogenesis of 60S ribosomal subunits, probably by acting as an rRNA helicase.
在欧洲功能分析网络的背景下，对酿酒酵母中一个以前未被鉴定的开放阅读框YNR038W进行了分析。YNR038W编码一种假定的DEAD-box蛋白家族的ATP依赖性RNA解旋酶，因此被命名为DBP6（DEAD-box蛋白6）。Dbp6p对细胞活力至关重要。体内Dbp6p的缺失会导致60S核糖体亚基的缺乏以及半聚核糖体的出现。通过Northern杂交和引物延伸对前体rRNA进行脉冲追踪标记以及对前体rRNA和成熟rRNA进行稳态分析表明，Dbp6p的缺失会导致27S和7S前体的产生减少，从而导致成熟的25S和5.8S rRNA的缺乏。此外，仅在核仁中检测到血凝素表位标记的Dbp6p。我们提出，Dbp6p可能通过作为rRNA解旋酶，在60S核糖体亚基的生物合成过程中，对前核糖体颗粒的正确组装是必需的。
