Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Minireview cung cấp cho các bạn kiến thức về ngành y đề tài: How to build a paraspeckle. | X Genome Biology Review How to build a paraspeckle Yasnory TF Sasaki and Tetsuro Hirose Address Functional RNomics Team Biomedicinal Information Research Center National Institute of Advanced Industrial Science and Technology AIST 2-42 Aomi Koutou Tokyo 135-0064 Japan. Email tets-hirose@ Abstract Noncoding RNAs have recently been identified as essential components of the nuclear suborganelles called paraspeckles. This finding will facilitate our understanding of the molecular dynamics and physiological role of these enigmatic macromolecular structures. Discovery of paraspeckles Paraspeckles are large ribonucleoprotein structures around pm in diameter that can be detected in nuclei with a light microscope and appropriate antibody staining and are currently of unknown function. They were discovered quite unexpectedly as recently as 2002 1 2 . Lamond and colleagues conducted a large-scale mass-spectrometric analysis of nucleoli isolated from HeLa cells which identified 271 nucleolar proteins. Of these proteins more than 30 were novel or uncharacterized 1 . The localization of a subset of the novel proteins fused with yellow fluorescent protein YFP for visual detection was then determined 2 . Surprisingly one of those fusion proteins was found to co-localize not to the nucleolus itself but to a novel nuclear compartment or suborganelle. The protein was found to be ubiquitously expressed in all human cell lines examined 2 and is localized in granular foci often adjacent to splicing-speckles which are implicated as the reservoir of various splicing factors. Hence the newly discovered foci were dubbed paraspeckles and the newly characterized protein was named paraspeckle protein 1 PSP1 2 . Mass spectrometric analysis of nucleolar proteins demonstrated that a small fraction of this protein undetectable by fluorescence microscopy transiently associated with the nucleolus which explained its original detection as a nucleolar protein 1 .
