Cavallaro, Massimo, Wang, Yuexuan, Hebenstreit, Daniel and Dutta, Ritabrata

Transcription is a complex phenomenon that permits the conversion of genetic information into phenotype by means of an enzyme called RNA polymerase, which erratically moves along and scans the DNA template. We perform Bayesian inference over a paradigmatic mechanistic model of non-equilibrium statistical physics, i.e. the asymmetric exclusion processes in the hydrodynamic limit, assuming a Gaussian process prior for the polymerase progression rate as a latent variable. Our framework allows us to infer the speed of polymerases during transcription given their spatial distribution, while avoiding the explicit inversion of the system’s dynamics. The results, which show processing rates strongly varying with genomic position and minor role of traffic-like congestion, may have strong implications for the understanding of gene expression.

Royal Society Open Science. August 2023

Tayseer Jibreel, Altayeb Khogali, Maribel Jiménez, Raiyed, Adeel, Osman Dakein, Bashir Alsharif, Noteila M. Khalid, Omran F. Osman, Bakri Y M Nour, Gamal Hassan Mohamed, Ricardo Molina, Ana Vidal, Ramón Díaz-Regañón, Margriet den Boer, Jorge Alvar, Orin Courtenay, D. A. Elnaiem

Visceral leishmaniasis (VL, kala azar), caused by Leishmania donovani, transmitted by Phlebotomus orientalis, is a serious systemic disease that causes high morbidity and mortality rates in Sudan and other parts of East Africa and the world. Despite progress in understanding the epidemiology of the disease in East Africa, little is known about the host preference of P. orientalis in kala azar endemic villages of Sudan, which have some of the highest VL incidence rates in the world. The present study used host choice experiments and blood-meal identification approaches to determine the host preference of P. orientalis in kala azar endemic villages in Gedarif state, eastern Sudan. Although the order of host preference varied by location, it was clear that cows are the most preferred host of P. orientalis in the area. Results are discussed in relation to the role of domestic/livestock animals in VL zoopotentiation and zooprophylaxis. Inference is made on the potential impact of insecticide treatment of cows in control of the vector and the transmission of VL in Sudan and other parts of East Africa.

Medical and Veterinary Entomology. August 2023

Björn Nitzsche, Sabine Schulze, Johannes Boltze, Martin J. Schmidt

Pathomorphological alterations of the central nervous system in dogs, such as syringomyelia and Chiari-like malformation, can cause cranial and cervical hyperesthesia and neuropathic pain. The long-term activity of the pain network can induce functional alteration and eventually even morphological changes in the pain network. This may happen especially in the prefrontal and cingulate cortex, where atrophy of the gray matter (GM) was observed in humans with chronic pain, irrespective of the nature of the pain syndrome. We tested the hypothesis that Cavalier King Charles Spaniels (CKCS) with Chiari-like malformation and associated syringomyelia (SM) and pain show cerebral morphological differences compared to animals without signs of syringomyelia and pain. We found that GM atrophy in the CG is associated with chronic pain and thus may serve as an objective readout parameter for the diagnosis or treatment of canine pain syndromes.

Frontiers in Neuroanatomy. July 2023

Kelsey Cremin, Gabriel N Meloni, Dimitrios Valavanis, Orkun S Soyer and Patrick R Unwin

Ultramicroelectrode (UME), or, equivalently, microelectrode, probes are increasingly used for single-cell measurements of cellular properties and processes, including physiological activity, such as metabolic fluxes and respiration rates. Major challenges for the sensitivity of such measurements include: (i) the relative magnitude of cellular and UME fluxes (manifested in the current); and (ii) issues around the stability of the UME response over time. To explore the extent to which these factors impact the precision of electrochemical cellular measurements, we undertake a systematic analysis of measurement conditions and experimental parameters for determining single cell respiration rates via the oxygen consumption rate (OCR) in single HeLa cells. We provide a set of model-based suggestions for improving these measurements in the future but highlight that extraordinary improvements in the stability and precision of SECM measurements will be required if single cell OCR measurements are to be realized.

ACS Measurement Science. July 2023

Masahiro Oka, Mayumi Otani, Yoichi Miyamoto, Rieko Oshima, Jun Adachi, Takeshi Tomonaga, Munehiro Asally, Yuya Nagaoka, Kaori Tanaka, Atsushi Toyoda, Kazuki Ichikawa, Shinichi Morishita, Kyoichi Isono, Haruhiko Koseki, Ryuichiro Nakato, Yasuyuki Ohkawa, Yoshihiro Yoneda

NUP98 and NUP214 form chimeric fusion proteins that assemble into phase-separated nuclear bodies containing CRM1, a nuclear export receptor. However, these nuclear bodies' function in controlling gene expression remains elusive. Here, we demonstrate that the nuclear bodies of NUP98::HOXA9 and SET::NUP214 promote the condensation of mixed lineage leukemia 1 (MLL1), a histone methyltransferase essential for the maintenance of HOX gene expression. Collectively, our results show that the phase-separated nuclear bodies of nucleoporin fusion proteins can enhance the activation of target genes by promoting the condensation of MLL1/CRM1 and rearrangement of the 3D genome structure.

Cell Reports. July 2023

Monica Garcia-Durillo and Bruno. G. Frenguelli  

Approximately 30% of patients with status epilepticus (SE) become refractory to two or more antiseizure medications (ASM). There is thus a real need to identify novel targets to develop new ASMs for treating this clinical emergency. This study evaluated the effect of the selective P2X7R antagonist A740003 on acute seizures in the dentate gyrus (DG) of hippocampal brain slices, where P2X7Rs are highly expressed, with a view to establishing its potential use as a therapy or adjunct with lorazepam (LZP) in refractory SE.. Our study revealed that, in the absence of changes in mRNA for P2X7Rs or inflammatory markers, P2X7R antagonism did not alter the frequency of SLEs. However, A740003 in conjunction with LZP delayed the onset of seizures. Furthermore, our results support the need for employing LZP before seizures become refractory during SE (i.e., in the 60 min frame since first seizure appears) as delayed of application LZP increased seizure frequency. These studies reveal possible sites of intervention that could have a positive impact in patients with high risk of suffering SE or its drug-refractory variant.

Neuropharmacology. July 2023