Three-dimensional structural analysis of mitochondria composing each subtype of fast-twitch muscle fibers in chicken

The Journal of Veterinary Medical Science

article

Sachi MAKIDA¹  Kiyokazu KAMETANI¹  Marina HOSOTANI¹  Naoki TAKAHASHI²  Tomohito IWASAKI³  Yasuhiro HASEGAWA³  Tomohide TAKAYA⁴  Hiromi UEDA¹  Takafumi WATANABE¹ 

[1] Department of Veterinary Anatomy, School of Veterinary Medicine, Rakuno Gakuen University;Department of Veterinary Anatomy, College of Bioresource Sciences, Nihon University;Department of Food Science and Human Wellness, College of Agriculture, Food and Environment Science, Rakuno Gakuen University;Department of Agricultural and Life Sciences, Faculty of Agriculture, Shinshu University

关键词: array tomography;    correlative light electron microscopy;    electron microscopy;    fast skeletal muscle;    mitochondria;   

DOI  :  10.1292/jvms.22-0080

学科分类：兽医学

来源: Japanese Society of Veterinary Science

【 摘 要 】

In a previous study, the three-dimensional structures of mitochondria in type I and type IIb muscle fibers of chicken were analyzed. The study reported differences in the shape of the mitochondria and the distribution of lipid droplets. In this study, we three-dimensionally analyzed mitochondria and lipid droplets of type II muscle fiber subtypes IIa, IIb, and IIc of chicken lateral iliotibial muscle in the same field of view using correlative light electron microscopy (CLEM) and array tomography methods. The reconstructed images showed that the mitochondria of type IIa muscle fiber were thick and aligned along the myofibrils, and many lipid droplets were embedded in the mitochondria. The mitochondria of type IIb muscle fibers were intermittent, aligned along the myofibrils, and showed contact between adjacent horizontal mitochondria. No lipid droplets were observed in type IIb muscle fiber. In type IIc muscle fiber, we observed irregularly shaped mitochondria with small diameters aligned along the myofibrils. Lipid droplets not only were embedded in the mitochondria but also existed independently in some cases. The combination of array tomography and CLEM methods enabled three-dimensional electron microscopic observation of mitochondria in different subtypes of type II muscle fibers. The subtypes of type II muscle fibers differed in mitochondrial occupancy and morphology and in lipid droplet distribution, and characteristics that had been demonstrated biochemically were also demonstrated ultrastructurally.

【 授权许可】

Unknown