title: MICAL-like Regulates Fasciclin II Membrane Cycling and Synaptic Development.
abstract: Fasciclin II (FasII), theDrosophilaortholog of neural cell adhesion molecule (NCAM), plays a critical role in synaptic stabilization and plasticity. Although this molecule undergoes constitutive cycling at the synaptic membrane, how its membrane trafficking is regulated to ensure proper synaptic development remains poorly understood. In a genetic screen, we recovered a mutation inDrosophila mical-likethat displays an increase in bouton numbers and a decrease in FasII levels at the neuromuscular junction (NMJ). Similar phenotypes were induced by presynaptic, but not postsynaptic, knockdown ofmical-likeexpression. FasII trafficking assays revealed that the recycling of internalized FasII molecules to the cell surface was significantly impaired inmical-like-knockdown cells. Importantly, this defect correlated with an enhancement of endosomal sorting of FasII to the lysosomal degradation pathway. Similarly, synaptic vesicle exocytosis was also impaired inmical-likemutants. Together, our results identify Mical-like as a novel regulator of synaptic growth and FasII endocytic recycling.
authors: Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Korea.|School of Dentistry and Dental Research Institute, Seoul National University, Seoul 08826, Korea.
authors: Minyeop
authors: M
authors: Nahm
authors: Interdisciplinary Graduate Program in Brain Science, College of Natural Sciences, Seoul National University, Seoul 08826, Korea.
authors: Sunyoung
authors: S
authors: Park
authors: Department of Oral Pathology and BK21 PLUS Project, School of Dentistry and Institute of Translational Dental Sciences, Pusan National University, Yangsan 50612, Korea.
authors: Jihye
authors: J
authors: Lee
authors: Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Korea.|School of Dentistry and Dental Research Institute, Seoul National University, Seoul 08826, Korea.|Interdisciplinary Graduate Program in Brain Science, College of Natural Sciences, Seoul National University, Seoul 08826, Korea.
authors: Seungbok
authors: S
authors: Lee
mesh_terms: D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004330:Drosophila; D013569:Synapses / Q000378:metabolism*; D009435:Synaptic Transmission
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; D004268:DNA-Binding Proteins; C496247:MICAL protein, Drosophila; C051642:fasciclin II
keywords: Drosophila; FasII endocytic recycling; MICAL-like; neuromuscular junction; synaptic growth