Voltage-dependent Ca2+ channels (VDCCs) mediate neurotransmitter release controlled by presynaptic proteins such as the scaffolding proteins Rab3-interacting molecules (RIMs). RIMs confer sustained activity and anchoring of synaptic vesicles to the VDCCs. Multiple sites on the VDCC α1 and β subunits have been reported to mediate the RIMs-VDCC interaction, but their significance is unclear. Because alternative splicing of exons 44 and 47 in the P/Q-type VDCC α1 subunit CaV2.1 gene generates major variants of the CaV2.1 C-terminal region, known for associating with presynaptic proteins, we focused here on the protein regions encoded by these two exons. Co-immunoprecipitation experiments indicated that the C-terminal domain (CTD) encoded by CaV2.1 exons 40-47 interacts with the α-RIMs, RIM1α and RIM2α, and this interaction was abolished by alternative splicing that deletes the protein regions encoded by exons 44 and 47. Electrophysiological characterization of VDCC currents revealed that the suppressive effect of RIM2α on voltage-dependent inactivation (VDI) was stronger than that of RIM1α for the CaV2.1 variant containing the region encoded by exons 44 and 47. Importantly, in the CaV2.1 variant in which exons 44 and 47 were deleted, strong RIM2α-mediated VDI suppression was attenuated to a level comparable with that of RIM1α-mediated VDI suppression, which was unaffected by the exclusion of exons 44 and 47. Studies of deletion mutants of the exon 47 region identified 17 amino acid residues on the C-terminal side of a polyglutamine stretch as being essential for the potentiated VDI suppression characteristic of RIM2α. These results suggest that the interactions of the CaV2.1 CTD with RIMs enable CaV2.1 proteins to distinguish α-RIM isoforms in VDI suppression of P/Q-type VDCC currents.
Under the COVID-19 pandemic, various electronic labeling initiatives have accelerated worldwide in the healthcare and pharmaceutical fields as part of a wider digital transformation [1, 2]. Although there is no universal definition of electronic labeling (e-labeling) globally, it is widely understood that e-labeling refers to the product information that is distributed via electronic means. There are 5 factors to be considered in e-labeling, and these are discussed in this publication. APAC is an industry-driven initiative with 13 R&D-based pharmaceutical associations joining from 11 markets in Asia. e-labeling was discussed as a new topic starting in 2020, and a 22-question survey was conducted in November 2021 to understand the current e-labeling status. The survey results showed that e-labeling initiatives were at different levels of maturity in the Asian region, although most markets have started to discuss e-labeling initiatives. Various challenges exist around e-labeling initiatives due to a variety of different approaches being taken in the region. It would be advisable to develop regional guidance on how to proceed with e-labeling initiatives in the Asian region to have a consistent and efficient approach. The close collaboration between agencies, Health Care Professionals (HCPs), patients, and industry associations is important to move e-labeling initiatives forward in Asia.
Rheumatoid arthritis (RA) is a highly heritable complex disease with unknown etiology. Multi-ancestry genetic research of RA promises to improve power to detect genetic signals, fine-mapping resolution and performances of polygenic risk scores (PRS). Here, we present a large-scale genome-wide association study (GWAS) of RA, which includes 276,020 samples from five ancestral groups. We conducted a multi-ancestry meta-analysis and identified 124 loci (P