title: Cylindrical Spirals in Skeletal Muscles Originate From the   Longitudinal Sarcoplasmic Reticulum.
abstract: Cylindrical spirals (CSs) are rare but distinct subsarcolemmal accumulations in skeletal muscle fibers. To date, CSs have been reported in only 16 patients with a variety of neuromuscular conditions. The origin and composition of CSs are unknown, although there are some morphologic similarities between CSs and tubular aggregates (TAs). To clarify the nature of CSs, we characterized the sarcoplasmic reticulum (SR) and other intracellular membrane system proteins in CSs of muscle biopsies from 2 adult Chinese siblings. Immunohistochemical studies revealed subsarcolemmal immunoreactivity for sarco/endoplasmic reticulum Ca2þ-ATPase 1 (SERCA 1) in the longitudinal SR, but no immunoreactivity for calsequestrin in the terminal cisternae or type 1 ryanodine receptor (RYR1) in the junctional SR. Muscles biopsied from 2 patients with TAs showed immunoreactivity not only for SERCA1 but also for other SR proteins, including calsequestrin and RYR1. CSs exhibited no immunoreactivity for the Golgi apparatus marker GM130, the nuclear membrane emerin, desmin, the autophagosome marker LC3, the lysosomal membrane marker LAMP2, dystrophin, or myosin. Our results suggest CSs may originate only from the longitudinal SR, whereas TAs are composed of both the junctional and longitudinal SR. Immunochemical staining with antibodies against calsequestrin and RYR1 help to distinguish these 2 pathological alterations.
authors.forename: Jing-Wen
authors.initials: JW
authors.lastname: Xu
authors.forename: Fu-Chen
authors.initials: FC
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Yu-Ying
authors.initials: YY
authors.lastname: Zhao
authors.forename: Dan-Dan
authors.initials: DD
authors.lastname: Zhao
authors.forename: Yue-Bei
authors.initials: YB
authors.lastname: Luo
authors.forename: Jian-Qiang
authors.initials: JQ
authors.lastname: Lu
authors.forename: Chuan-Zhu
authors.initials: CZ
authors.lastname: Yan
mesh_terms: D000328:Adult; D044466:Asian People; D015220:Calcium Channels / Q000096:biosynthesis / Q000235:genetics; D015815:Cell Adhesion Molecules / Q000096:biosynthesis / Q000235:genetics; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics; D008875:Middle Aged; D018485:Muscle Fibers, Skeletal / Q000473:pathology / Q000648:ultrastructure*; D018482:Muscle, Skeletal / Q000473:pathology / Q000648:ultrastructure*; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D009468:Neuromuscular Diseases / Q000235:genetics / Q000473:pathology; D000071740:ORAI1 Protein; D012508:Sarcolemma / Q000235:genetics / Q000473:pathology / Q000648:ultrastructure*; D012519:Sarcoplasmic Reticulum / Q000235:genetics / Q000473:pathology / Q000648:ultrastructure*; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000096:biosynthesis / Q000235:genetics; D000071737:Stromal Interaction Molecule 1; D000071738:Stromal Interaction Molecule 2
chemical_list: D015220:Calcium Channels; D015815:Cell Adhesion Molecules; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D000071740:ORAI1 Protein; C510746:ORAI1 protein, human; C103530:STIM1 protein, human; C513279:STIM2 protein, human; D000071737:Stromal Interaction Molecule 1; D000071738:Stromal Interaction Molecule 2; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; C506943:ATP2A1 protein, human