title: Spatially distinct mitochondrial populations exhibit different mitofilin levels.
abstract: Subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondria exhibit unique biochemical and functional properties; however, their association with structural membrane proteins that control mitochondrial morphology and functionality in striated muscle tissue was never reported. In IMF and SS mitochondria isolated from rat heart and gastrocnemius muscle, we analysed the expression levels of mitofilin, a mitochondria-associated protein involved in organelle structure maintenance. The statistically significant higher amounts of mitofilin detected in IMF compared with SS mitochondria, 37-fold in cardiac tissue and 3.8-fold in gastrocnemius, together with the specific energetic requirements of these mitochondrial populations highlight the importance of mitofilin in oxidative phosphorylation functionality and in mitochondrial plasticity in striated muscle. The differential expression levels of mitofilin between IMF and SS also suggest that this protein can be used as a specific molecular marker to comparatively discriminate spatially distant mitochondrial populations.
authors.affiliation: QOPNA, Department of Chemistry, University of Aveiro, Aveiro, Portugal.
authors.forename: Rita M P
authors.initials: RM
authors.lastname: Ferreira
authors.forename: Rui
authors.initials: R
authors.lastname: Vitorino
authors.forename: Ana Isabel
authors.initials: AI
authors.lastname: Padrão
authors.forename: Daniel
authors.initials: D
authors.lastname: Moreira-Gonçalves
authors.forename: Renato M P
authors.initials: RM
authors.lastname: Alves
authors.forename: José Alberto
authors.initials: JA
authors.lastname: Duarte
authors.forename: Francisco
authors.initials: F
authors.lastname: Amado
mesh_terms: D000818:Animals; D008297:Male; D008929:Mitochondria, Heart / Q000378:metabolism; D008931:Mitochondria, Muscle / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism*; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000166:cytology; D009210:Myofibrils; D051381:Rats; D017208:Rats, Wistar
chemical_list: C588360:Immt protein, rat; D024101:Mitochondrial Proteins; D009124:Muscle Proteins