Designing a high-throughput screen for small molecule modulators of the molecular motor KIF1A

The neuron-specific kinesin, KIF1A, is involved in the transport of cargos critical for neuronal function such as synaptic vesicle precursors and dense-core vesicles. Notably, mutations in KIF1A are implicated in the pathogenesis of neurological disorders such as hereditary spastic paraplegia. Therapies that specifically target KIF1A do not currently exist. I developed a high-throughput, phenotypic screen for small molecule modulators of KIF1A. I used two-color fluorescent imaging to identify a cell-based, phenotypic assay that allows for characterization of the inactive, autoinhibited form of KIF1A and the active form of KIF1A. When expressed in COS-7 and SK-N-SH cells, wild-type KIF1A-GFP is diffusely distributed and does not co-localize with the microtubule marker EB3-mKate2. The hyperactive mutant V8M KIF1A-GFP does co-localize with microtubules and distributes peripherally. These findings support the feasibility of a functional assay to distinguish between the active and inactive forms of KIF1A in a high-throughput screening format

Going Too Far Is the Same as Falling Short: Kinesin-3 Family Members in Hereditary Spastic Paraplegia

Proper intracellular trafficking is essential for neuronal development and function, and when any aspect of this process is dysregulated, the resulting “transportopathy” causes neurological disorders. Hereditary spastic paraplegias (HSPs) are a family of such diseases attributed to over 80 spastic gait genes (SPG), specifically characterized by lower extremity spasticity and weakness. Multiple genes in the trafficking pathway such as those relating to microtubule structure and function and organelle biogenesis are representative disease loci. Microtubule motor proteins, or kinesins, are also causal in HSP, specifically mutations in Kinesin-I/KIF5A (SPG10) and two kinesin-3 family members; KIF1A (SPG30) and KIF1C (SPG58). KIF1A is a motor enriched in neurons, and involved in the anterograde transport of a variety of vesicles that contribute to pre- and post-synaptic assembly, autophagic processes, and neuron survival. KIF1C is ubiquitously expressed and, in addition to anterograde cargo transport, also functions in retrograde transport between the Golgi and the endoplasmic reticulum. Only a handful of KIF1C cargos have been identified; however, many have crucial roles such as neuronal differentiation, outgrowth, plasticity and survival. HSP-related kinesin-3 mutants are characterized mainly as loss-of-function resulting in deficits in motility, regulation, and cargo binding. Gain-of-function mutants are also seen, and are characterized by increased microtubule-on rates and hypermotility. Both sets of mutations ultimately result in misdelivery of critical cargos within the neuron. This likely leads to deleterious cell biological cascades that likely underlie or contribute to HSP clinical pathology and ultimately, symptomology. Due to the paucity of histopathological or cell biological data assessing perturbations in cargo localization, it has been difficult to positively link these mutations to the outcomes seen in HSPs. Ultimately, the goal of this review is to encourage future academic and clinical efforts to focus on “transportopathies” through a cargo-centric lens

Tumor expression of survivin, p53, cyclin D1, osteopontin and fibronectin in predicting the response to neo-adjuvant chemotherapy in children with advanced malignant peripheral nerve sheath tumor

Purpose Selected cell-cycle regulators and extracellular matrix proteins were found to play roles in malignant peripheral nerve sheath tumor (MPNST) biology. We aimed to analyze whether initial tumor tissue expressions of survivin, p53, cyclin D1, osteopontin (OPN) and fibronectin (FN) correlate with the response to neo-adjuvant CHT (naCHT) in children with advanced inoperable MPNST. Methods The study included 26 children with MPNST (M/F 14/12, median age 130 months) treated in Polish centers of pediatric oncology between 1992 and 2013. Tissue expression of markers was studied immunohistochemically in the manually performed tissue microarrays and assessed semi-quantitatively as low and high, based on the rate of positive cells and staining intensity. Results Good response to naCHT was noted in 47.6%, while poor-in 52.4% of patients. The response to naCHT was influenced negatively by the presence of neurofibromatosis NF1 and high initial tumor tissue expression of OPN, survivin, p53 and cyclin D1. Patients with high tumor expression of either OPN, survivin or p53 and those with simultaneous high expression of ≥ 3 of the markers, responded significantly worse to naCHT, than patients, in whom expression of ≤ 2 markers were detected at diagnosis. Nearly, 85% of patients expressing ≥ 3 markers, responded poor to CHT; while 87.5% of children, expressing ≤ 2 markers, were good responders. Conclusion The initial tumor tissue expression of OPN, survivin, p53 and cyclin D1 may serve as markers to predict response to naCHT in pediatric advanced MPNST. Future studies in more numerous group of patients are needed to confirm these preliminary results

Quality assessment of interpreting in Polish-English police-suspect interviews. A multi-method study.

Quality in interpreting has been investigated from different perspectives with the main focus being put on conference interpreting. Little research has been conducted on assessing the quality of interpreting in public service settings, more specifically, in legal settings, and in particular within police interpreting. The introduction of the Directive 2010/64/EU of the European Parliament and the European Council, which was established with the intention of strengthening language rights, was a positive development that put more emphasis on quality in legal interpreting, calling for improved quality standards along with more research into interpreting quality in public service interpreting contexts. In the United Kingdom, the introduction of the Framework Agreement for interpreting and translation services has not helped to implement the Directive. The dilution of existing standards and procedures for interpreter recruitment in the legal setting, has had drastic effects on interpreting quality and service provision. Therefore, research is imperative, especially research into factors that influence interpreting quality in public service interpreting, in order to create an evidence base. In this context, this experimental study based on simulated data examines the quality of interpreting in the police setting by analysing the performance of interpreters with different professional profiles. It seeks to determine the factors that influence the quality of interpreting and establish links between interpreters’ profiles and their performance. To achieve its aims, the study includes nine interpreters and adopts a multi-method approach, combining qualitative and quantitative empirical investigations of the interpreters’ performance (output quality) with data elicited in reflective sessions and a questionnaire-based analysis of the interpreters’ profiles. The study employs pre-experiment questionnaires that provide information on interpreters’ backgrounds, it analyses the interpreters’ performance in simulated police-suspect interviews against a set of criteria that were devised to evaluate interpreting quality in the legal context. It also employs post-experiment retrospective think-aloud protocols to gain additional insights into the interpreters’ decision-making mechanisms. Through employing a multi-method approach and by creating a model for assessing the quality in the legal settings, the present study complements and extends recent studies on police interpreting conducted by Böser (2013), Braun (2013) or Gallai (2017) and provides a better understanding of factors which influence the quality of interpreting

Microbiome impact on metabolism and function of sex, thyroid, growth and parathyroid hormones

Commensal bacteria and their genes associated with host are known as microbiome. In recent years, microbial influence on host endocrine system has been under detailed investigation. The role of microbiome in the pathogenesis of insulin resistance and obesity, the function of hypothalamic-pituitary-adrenal axis and secretion of hormones regulating appetite is well described in world literature. In this article we discuss poorly reviewed issues: the microbiome role in modulation of non-peptide (sex and thyroid) and peptide (growth hormone and parathyroid hormone) functions. Understanding complex bidirectional relations between host endocrine system and bacteria is of fundamental importance to understanding microbial impact on host reproduction, risk of endocrine-related cancers, pathogenesis of non-thyroidal illness syndrome, growth failure in children and hormonal changes during chronic kidney disease. This article also highlights effects of dietary compounds on microbiome composition and bacterial enzymes activity, and thus host hormonal status

Loss of E-Cadherin Staining Continuity in the Trophoblastic Basal Membrane Correlates with Increased Resistance in Uterine Arteries and Proteinuria in Patients with Pregnancy-Induced Hypertension

Pregnancy-induced hypertension (PIH), especially when complicated with pre-eclampsia (PE), could be a life-threatening complication of pregnancy. Pre-eclampsia is one of the leading causes of perinatal morbidity and mortality in women. Pre-eclampsia is mainly characterized by hypertension and kidney damage with proteinuria. Abnormal placentation and altered structure of the placental barrier are believed to participate in the pathogenesis of pregnancy-induced hypertension, leading to PE. In the current study, we aimed to analyze the immunohistochemical expression pattern of E-cadherin and p120, two markers of epithelial–mesenchymal transition, in placental samples derived from a group of 55 patients with pregnancy-induced hypertension, including pre-eclampsia and 37 healthy pregnant controls. The results were correlated with the presence of an obtained early uterine artery flow notching during diastole on Doppler ultrasound. We observed a higher frequency of discontinuous E-cadherin staining in the basement membrane of syncytiotrophoblast in patients with PIH/PE compared to controls (p p p = 0.013, Fisher’s exact test). These findings suggest that E-cadherin contributes to the integrity of the placental barrier, and its loss could be an immunohistochemical marker of PE

Testicular teratoma with nephroblastoma in an adult – case report and literature review

Testicular germ cell tumours are the most common malignancies in young men. Germ cell tumours can be classified as seminomas or non-seminomas, each with different clinical features and treatment approaches. Germ cell tumours are occasionally associated with somatic-type malignancy, particularly in metastatic lymph nodes after adjuvant chemotherapy. Adenocarcinomas and rhabdomyosarcoma are the most common malignancies in this setting. In this report, we present a unique case of a 37-year-old patient who presented with a testicular teratoma containing a nephroblastoma component. The tumour exhibited characteristic morphology that resembled foetal kidney and expressed nuclear WT-1 and PAX-8 on immunohistochemistry. Following surgery, the patient opted for active surveillance and remains disease-free. To date, only 7 cases of nephroblastoma in primary testicular teratoma have been reported. This case highlights the importance of considering this rare entity in the differential diagnosis of testicular teratomas and the need for careful pathological examination

GSK3β Impairs KIF1A Transport in a Cellular Model of Alzheimer’s Disease but Does Not Regulate Motor Motility at S402

Impairment of axonal transport is an early pathologic event that precedes neurotoxicity in Alzheimer’s disease (AD). Soluble amyloid-β oligomers (AβOs), a causative agent of AD, activate intracellular signaling cascades that trigger phosphorylation of many target proteins, including tau, resulting in microtubule destabilization and transport impairment. Here, we investigated how KIF1A, a kinesin-3 family motor protein required for the transport of neurotrophic factors, is impaired in mouse hippocampal neurons treated with AβOs. By live cell imaging, we observed that AβOs inhibit transport of KIF1A-GFP similarly in wild-type and tau knock-out neurons, indicating that tau is not required for this effect. Pharmacological inhibition of glycogen synthase kinase 3β (GSK3β), a kinase overactivated in AD, prevented the transport defects. By mass spectrometry on KIF1A immunoprecipitated from transgenic AD mouse brain, we detected phosphorylation at S402, which conforms to a highly conserved GSK3β consensus site. We confirmed that this site is phosphorylated by GSK3β in vitro. Finally, we tested whether a phosphomimic of S402 could modulate KIF1A motility in control and AβO-treated mouse neurons and in a Golgi dispersion assay devoid of endogenous KIF1A. In both systems, transport driven by mutant motors was similar to that of WT motors. In conclusion, GSK3β impairs KIF1A transport but does not regulate motor motility at S402. Further studies are required to determine the specific phosphorylation sites on KIF1A that regulate its cargo binding and/or motility in physiological and disease states