14 research outputs found
Nucleolus: the fascinating nuclear body
Nucleoli are the prominent contrasted structures of the cell nucleus. In the nucleolus, ribosomal RNAs are synthesized, processed and assembled with ribosomal proteins. RNA polymerase I synthesizes the ribosomal RNAs and this activity is cell cycle regulated. The nucleolus reveals the functional organization of the nucleus in which the compartmentation of the different steps of ribosome biogenesis is observed whereas the nucleolar machineries are in permanent exchange with the nucleoplasm and other nuclear bodies. After mitosis, nucleolar assembly is a time and space regulated process controlled by the cell cycle. In addition, by generating a large volume in the nucleus with apparently no RNA polymerase II activity, the nucleolus creates a domain of retention/sequestration of molecules normally active outside the nucleolus. Viruses interact with the nucleolus and recruit nucleolar proteins to facilitate virus replication. The nucleolus is also a sensor of stress due to the redistribution of the ribosomal proteins in the nucleoplasm by nucleolus disruption. The nucleolus plays several crucial functions in the nucleus: in addition to its function as ribosome factory of the cells it is a multifunctional nuclear domain, and nucleolar activity is linked with several pathologies. Perspectives on the evolution of this research area are proposed
Patch-Scale Relationships Between Geodiversity and Biodiversity in Hard Rock Quarries: Case Study from a Disused Quartzite Quarry in NW France
Antibiotic Prophylaxis in Transcatheter Treatment of Hepatocellular Carcinoma: an Open Randomized Prospective Study of Oral Versus Intravenous Administration
A Pseudo MS3 Approach for Identification of Disulfide-Bonded Proteins: Uncommon Product Ions and Database Search
Organization of the amplified type I interferon gene cluster and associated chromosome regions in the interphase nucleus of human osteosarcoma cells
Fragmentation Follows Structure: Top-Down Mass Spectrometry Elucidates the Topology of Engineered Cystine-Knot Miniproteins
Dynamic Behavior of the RNA Polymerase II and the Ubiquitin Proteasome System During the Neuronal DNA Damage Response to Ionizing Radiation
MALDI In-Source Decay, from Sequencing to Imaging
peer reviewedMALDI is now a mature method allowing the identification and, more challenging, the quantification of biopolymers (proteins, nucleic acids, glycans…). MALDI spectra show mostly intact singly charged ions. To obtain fragments, the activation of singly charged precursors is necessary, but not efficient above 3.5 kDa thus making MALDI MS/MS difficult for large species. In-source decay (ISD) is a prompt fragmentation reaction that can be induced thermally or by radicals. As fragments are formed in the source, precursor ions cannot be selected; however, the technique is not limited by the mass of the analyzed compounds and pseudo MS/MS can be performed on intense fragments. The discovery of new matrices that enhance the ISD yield, combined with the high sensitivity of MALDI mass spectrometers, and software development, opens new perspectives. We first review the mechanisms involved in the ISD processes, then discuss ISD applications like top-down sequencing and post-translational modifications studies, and finally review MALDI-ISD tissue imaging applications