Messenger ribonucleoprotein particles (mRNPs) move randomly within nucleoplasm before they exit from the nucleus. To further understand mRNP trafficking, we have studied the intranuclear movement of a specific mRNP, the BR2 mRNP, in salivary gland cells in Chironomus tentans. Their polytene nuclei harbor giant chromosomes separated by vast regions of nucleoplasm, which allows us to study mRNP mobility without interference of chromatin. The particles were fluorescently labeled with microinjected oligonucleotides (DNA or RNA) complementary to BR2 mRNA or with the RNA-binding protein hrp36, the C. tentans homologue of hnRNP A1. Using high-speed laser microscopy, we followed the intranuclear trajectories of single mRNPs and characterized their motion within the nucleoplasm. The Balbiani ring (BR) mRNPs moved randomly, but unexpectedly, in a discontinuous manner. When mobile, they diffused with a diffusion coefficient corresponding to their size. Between mobile phases, the mRNPs were slowed down 10- to 250-fold but were never completely immobile. Earlier electron microscopy work has indicated that BR particles can attach to thin nonchromatin fibers, which are sometimes connected to discrete fibrogranular clusters. We propose that the observed discontinuous movement reflects transient interactions between freely diffusing BR particles and these submicroscopic structures.
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http://dx.doi.org/10.1073/pnas.0810692105 | DOI Listing |
Sci Rep
January 2025
Department of Growth and Development, University of Nebraska Medical Center, 4000 East Campus Loop South, 68583-0740, Lincoln, NE, US.
Osteogenesis imperfecta (OI) is a fairly common generalized connective disorder characterized by low bone mass, bone deformities and impaired bone quality that predisposes affected individuals to musculoskeletal fragility. Periodontal ligament (PDL)-alveolar bone and PDL-cementum entheses' roles under OI conditions during physiological loading and orthodontic forces remain largely unknown. In addition, bisphosphonates (e.
View Article and Find Full Text PDFPaediatr Anaesth
December 2024
Department of Neonatal and Pediatric Intensive Care, Erasmus University Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands.
Background: The heart rate variability-based Newborn Infant Parasympathetic Evaluation (NIPE) Index is a continuous noninvasive tool for the assessment of pain and discomfort in infants. Little is known about its performance in the pediatric intensive care unit (PICU) setting, where assessment of pain/discomfort is usually based on discontinuous observational scoring systems or personal experience of medical staff.
Aim: Evaluation of the performance of NIPE as an indicator of procedural pain and/or discomfort in conscious mechanically ventilated PICU patients.
Commun Eng
December 2024
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
Sorption-based atmospheric water harvesting (SAWH) offers a promising solution to global water scarcity. However, practical implementation is limited by discontinuities in the mass transfer process inside sorbents. This perspective reviews current SAWH technologies and introduces a new concept, mass transfer of SAWH (MT-SAWH), which ensures continuous water collection by facilitating the movement of water molecules within a fixed sorbent bed.
View Article and Find Full Text PDFBrain Sci
October 2024
Department of Health & Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN 37403, USA.
Neural processes involved in visual detection, decision-making, and motor plan execution are believed to play a key role in the avoidance of sport-related injuries, but very little evidence exists to guide the development of training activities for the optimization of brain function. Immersive virtual reality provides a means to precisely measure the amount of time that elapses from visual stimulus presentation to the initiation of a motor response (i.e.
View Article and Find Full Text PDFOpen Res Eur
October 2024
National Agency of Hydrocarbon, Bogota, Cundinamarca, 111321, Colombia.
Background: The present contribution reexamines the geometry of a segment of a presumably long-lived fault in Svalbard, the Balliolbreen Fault segment of the Billefjorden Fault Zone, along which presumably two basement terranes of Svalbard accreted in the early-mid Paleozoic after thousands of kilometers strike-slip displacement.
Methods: We performed structural fieldwork to Billefjorden in central Spitsbergen and interpreted satellite images.
Results: Field observations demonstrate that the Balliolbreen Fault formed as a top-west thrust fault in the early Cenozoic and that weak sedimentary units such as shales of the Lower Devonian Wood Bay Formation and coals of the uppermost Devonian-Mississippian Billefjorden Group partitioned deformation, resulting in significant contrast in deformation intensity between stratigraphic units.
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