title: Smooth muscle titin forms in vitro amyloid aggregates.
abstract: Amyloids are insoluble fibrous protein aggregates, and their accumulation is associated with amyloidosis and many neurodegenerative diseases, including Alzheimer's disease. In the present study, we report that smooth muscle titin (SMT; 500 kDa) from chicken gizzard forms amyloid aggregates in vitro This conclusion is supported by EM data, fluorescence analysis using thioflavin T (ThT), Congo red (CR) spectroscopy and X-ray diffraction. Our dynamic light scattering (DLS) data show that titin forms in vitro amyloid aggregates with a hydrodynamic radius (Rh) of approximately 700-4500 nm. The initial titin aggregates with Rh approximately 700 nm were observed beyond first 20 min its aggregation that shows a high rate of amyloid formation by this protein. We also showed using confocal microscopy the cytotoxic effect of SMT amyloid aggregates on smooth muscle cells from bovine aorta. This effect involves the disorganization of the actin cytoskeleton and result is cell damage. Cumulatively, our results indicate that titin may be involved in generation of amyloidosis in smooth muscles.
authors.affiliation: Laboratory of Structure and Functions of Muscle Proteins, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation bobylev1982@gmail.com.
authors.forename: Alexandr G
authors.initials: AG
authors.lastname: Bobylev
authors.affiliation: Group of Bioinformatics, Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Oxana V
authors.initials: OV
authors.lastname: Galzitskaya
authors.affiliation: Laboratory of Structure and Functions of Muscle Proteins, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Roman S
authors.initials: RS
authors.lastname: Fadeev
authors.affiliation: Laboratory of Structure and Functions of Muscle Proteins, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Liya G
authors.initials: LG
authors.lastname: Bobyleva
authors.affiliation: Laboratory of Structure and Functions of Muscle Proteins, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Darya A
authors.initials: DA
authors.lastname: Yurshenas
authors.affiliation: Laboratory of Structure and Functions of Muscle Proteins, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Nikolay V
authors.initials: NV
authors.lastname: Molochkov
authors.affiliation: Group of Bioinformatics, Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Nikita V
authors.initials: NV
authors.lastname: Dovidchenko
authors.affiliation: Group of Bioinformatics, Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Olga M
authors.initials: OM
authors.lastname: Selivanova
authors.affiliation: Laboratory of Cryobiology and Biophysics of Water, Institute of Cell Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Nikita V
authors.initials: NV
authors.lastname: Penkov
authors.affiliation: Laboratory of Structure and Functions of Muscle Proteins, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Zoya A
authors.initials: ZA
authors.lastname: Podlubnaya
authors.affiliation: Laboratory of Structure and Functions of Muscle Proteins, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russian Federation.
authors.forename: Ivan M
authors.initials: IM
authors.lastname: Vikhlyantsev
mesh_terms: D000682:Amyloid / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D000818:Animals; D002417:Cattle; D002645:Chickens; D064211:Connectin / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D006801:Humans; D009130:Muscle, Smooth / Q000378:metabolism* / Q000473:pathology; D066329:Protein Aggregates; D066263:Protein Aggregation, Pathological / Q000378:metabolism* / Q000473:pathology; D017433:Protein Structure, Secondary
chemical_list: D000682:Amyloid; D064211:Connectin; D066329:Protein Aggregates
keywords: amyloid; amyloid aggregates; cytotoxicity; smooth muscle titin