Establishing a Mouse Genotyping Core Facility Based on Automation, High-resolution Melting Analysis, and Purpose-developed MATLAB Applications for Sample Tracking, Data Analysis, and Report Generation.

An in-house genotyping facility should aim to be more cost-effective than outsourced service and more reliable than genotyping performed by short-term employees or students of individual research groups. Reliable genotyping allows efficient and economical management of mice colonies and promotes accurate and reproducible research results. Here we provide a detailed description of our approach to establishing a genotyping core facility, relying on automated PCR assembly and high-resolution melting (HRM) analysis (first derivative). The workflow we devised was tightly managed by purpose-designed applications developed using MATLAB App Designer that allowed straightforward work planning, ensured sample tracking throughout the process, and provided a platform for reliable data analysis and generation of genotyping reports. We successfully transitioned PCR product analysis of more than 250 different target genes from standard gel electrophoresis to the more advanced HRM analysis. About 23% of the target genes required a redesign of primers to adapt to our protocol. The process was highly universal, and only 2% of the target genes required deviation from the standard PCR method to a more restricted protocol that reduces the amplification of nonspecific products. We currently run more than 1,000 PCR reactions weekly, of samples taken at weaning or experimental endpoint, and assemble a large variety of target genes in every PCR plate. We also showed that genotyping of blastocytes instead of embryos can serve as quality control of cryopreservation. Thus, our genotyping protocol promotes the 3Rs (Replacement, Reduction, and Refinement) principles. Our refined genotyping process facilitates cost-effective colony management, replaces tissue types as well as traditional methods with advanced ones, and provides reliable results in a timely manner. MATLAB codes and related data are available in supplementary materials and online.

10 K: a large-scale prospective longitudinal study in Israel.

The 10 K is a large-scale prospective longitudinal cohort and biobank that was established in Israel. The primary aims of the study include development of prediction models for disease onset and progression and identification of novel molecular markers with a diagnostic, prognostic and therapeutic value. The recruitment was initiated in 2018 and is expected to complete in 2021. Between 28/01/2019 and 13/12/2020, 4,629 from the expected 10,000 participants were recruited (46 %). Follow-up visits are scheduled every year for a total of 25 years. The cohort includes individuals between the ages of 40 and 70 years. Predefined medical conditions were determined as exclusions. Information collected at baseline includes medical history, lifestyle and nutritional habits, vital signs, anthropometrics, blood tests results, Electrocardiography, Ankle-brachial pressure index (ABI), liver US and Dual-energy X-ray absorptiometry (DXA) tests. Molecular profiling includes transcriptome, proteome, gut and oral microbiome, metabolome and immune system profiling. Continuous measurements include glucose levels using a continuous glucose monitoring device for 2 weeks and sleep monitoring by a home sleep apnea test device for 3 nights. Blood and stool samples are collected and stored at - 80 °C in a storage facility for future research. Linkage is being established with national disease registries.

The switching mechanism of the bacterial rotary motor combines tight regulation with inherent flexibility.

Regulatory switches are wide spread in many biological systems. Uniquely among them, the switch of the bacterial flagellar motor is not an on/off switch but rather controls the motor's direction of rotation in response to binding of the signaling protein CheY. Despite its extensive study, the molecular mechanism underlying this switch has remained largely unclear. Here, we resolved the functions of each of the three CheY-binding sites at the switch in E. coli, as well as their different dependencies on phosphorylation and acetylation of CheY. Based on this, we propose that CheY motor switching activity is potentiated upon binding to the first site. Binding of potentiated CheY to the second site produces unstable switching and at the same time enables CheY binding to the third site, an event that stabilizes the switched state. Thereby, this mechanism exemplifies a unique combination of tight motor regulation with inherent switching flexibility.

Rhodopsin and melanopsin coexist in mammalian sperm cells and activate different signaling pathways for thermotaxis.

Recently, various opsin types, known to be involved in vision, were demonstrated to be present in human and mouse sperm cells and to be involved there in thermosensing for thermotaxis. In vision, each opsin type is restricted to specific cells. The situation in this respect in sperm cells is not known. It is also not known whether or not both signaling pathways, found to function in sperm thermotaxis, are each activated by specific opsins, as in vision. Here we addressed these questions. Choosing rhodopsin and melanopsin as test cases and employing immunocytochemical analysis with antibodies against these opsins, we found that the majority of sperm cells were stained by both antibodies, indicating that most of the cells contained both opsins. By employing mutant mouse sperm cells that do not express melanopsin combined with specific signaling inhibitors, we furthermore demonstrated that rhodopsin and melanopsin each activates a different pathway. Thus, in mammalian sperm thermotaxis, as in vision, rhodopsin and melanopsin each triggers a different signaling pathway but, unlike in vision, both opsin types coexist in the same sperm cells.