The axon initial segment (AIS) is the site of action potential generation and a locus of activity-dependent homeostatic plasticity. A multimeric complex of sodium channels, linked via a cytoskeletal scaffold of ankyrin G and beta IV spectrin to submembranous actin rings, mediates these functions. The mechanisms that specify the AIS complex to the proximal axon and underlie its plasticity remain poorly understood. Here we show phosphorylated myosin light chain (pMLC), an activator of contractile myosin II, is highly enriched in the assembling and mature AIS, where it associates with actin rings. MLC phosphorylation and myosin II contractile activity are required for AIS assembly, and they regulate the distribution of AIS components along the axon. pMLC is rapidly lost during depolarization, destabilizing actin and thereby providing a mechanism for activity-dependent structural plasticity of the AIS. Together, these results identify pMLC/myosin II activity as a common link between AIS assembly and plasticity.
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http://dx.doi.org/10.1016/j.neuron.2017.12.039 | DOI Listing |
Int J Biol Macromol
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College of Food Science and Engineering, Inner Mongolia Agricultural University, 306 Zhaowuda Road, Hohhot, Inner Mongolia 010010, China. Electronic address:
Biodegradable plastics are increasingly utilized in packaging, driven by green chemistry and environmental responsibility. Among them, poly(L-lactic acid) (PLLA) stands out due to its biodegradability and biocompatibility. However, its limited gas permeability and selectivity hinder its application in produce preservation.
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Department of Materials Science and Engineering, School of Materials and Chemical Technology, Institute of Science Tokyo, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
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January 2025
Faculty of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031, China.
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March 2025
Department of Biomedical Engineering, College of Design and Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore; National University of Singapore (Suzhou) Research Institute, Suzhou, Jiangsu 215123, China; National University of Singapore (Chongqing) Research Institute, Yubei, Chongqing 401120, China; NUS Environmental Research Institute (NERI), National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore. Electronic address:
The combination of chemotherapy and gene therapy holds promise in treating cancer. A key strategy is to use small interfering RNAs (siRNAs) to silence programmed death-ligand 1 (PD-L1) expression in cancer cells, disrupting tumor immune evasion and enhancing anticancer treatments, particularly when used in conjunction with chemotherapy drugs such as doxorubicin (Dox). However, effective codelivery of drugs and genes requires carefully designed carriers and complex synthesis procedures.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Haiping Fang, School of Physics, East China University of Science and Technology, Shanghai, 20023, China.
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