Biomaterial Database

Molluscan twitchin can control actin-myosin interaction during ATPase cycle. 2010

Yurii S Borovikov, and Nikolay S Shelud'ko, and Stanislava V Avrova

Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia. boroviko@mail.cytspb.rssi.ru

The effect of twitchin, a thick filament protein of molluscan muscles, on actin-myosin interaction at several mimicked sequential steps of the ATPase cycle was investigated using fluorescent probes specifically bound to Cys707 of myosin subfragment-1 and Cys374 of actin incorporated into ghost muscle fibers. The multi-step changes in mobility and spatial arrangement of myosin SH1 helix and actin subdomain-1 during the ATPase cycle have been revealed. For the first time, the inhibition of movement of myosin SH1 helix and actin subdomain-1 during the ATPase cycle and the decrease in the myosin head and actin affinity in the presence of unphosphorylated twitchin have been demonstrated. Phosphorylation of twitchin by the catalytic subunit of protein kinase A reversed this effect. These data imply a novel property of twitchin consisting in its ability to regulate in a phosphorylation-dependent manner the actin-myosin interaction during the ATPase cycle by the inhibition of transformation of the weak-binding actomyosin states into the strong-binding ones.

UI	MeSH Term	Description	Entries
D008974	Mollusca	A phylum of the kingdom Metazoa. Mollusca have soft, unsegmented bodies with an anterior head, a dorsal visceral mass, and a ventral foot. Most are encased in a protective calcareous shell. It includes the classes GASTROPODA; BIVALVIA; CEPHALOPODA; Aplacophora; Scaphopoda; Polyplacophora; and Monoplacophora.	Molluscs,Mollusks,Mollusc,Molluscas,Mollusk
D009124	Muscle Proteins	The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.	Muscle Protein,Protein, Muscle,Proteins, Muscle
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D009218	Myosins	A diverse superfamily of proteins that function as translocating proteins. They share the common characteristics of being able to bind ACTINS and hydrolyze MgATP. Myosins generally consist of heavy chains which are involved in locomotion, and light chains which are involved in regulation. Within the structure of myosin heavy chain are three domains: the head, the neck and the tail. The head region of the heavy chain contains the actin binding domain and MgATPase domain which provides energy for locomotion. The neck region is involved in binding the light-chains. The tail region provides the anchoring point that maintains the position of the heavy chain. The superfamily of myosins is organized into structural classes based upon the type and arrangement of the subunits they contain.	Myosin ATPase,ATPase, Actin-Activated,ATPase, Actomyosin,ATPase, Myosin,Actin-Activated ATPase,Actomyosin ATPase,Actomyosin Adenosinetriphosphatase,Adenosine Triphosphatase, Myosin,Adenosinetriphosphatase, Actomyosin,Adenosinetriphosphatase, Myosin,Myosin,Myosin Adenosinetriphosphatase,ATPase, Actin Activated,Actin Activated ATPase,Myosin Adenosine Triphosphatase
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D000199	Actins	Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.	F-Actin,G-Actin,Actin,Isoactin,N-Actin,alpha-Actin,alpha-Isoactin,beta-Actin,gamma-Actin,F Actin,G Actin,N Actin,alpha Actin,alpha Isoactin,beta Actin,gamma Actin
D000205	Actomyosin	A protein complex of actin and MYOSINS occurring in muscle. It is the essential contractile substance of muscle.
D000251	Adenosine Triphosphatases	A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.	ATPases,Adenosinetriphosphatase,ATPase,ATPase, DNA-Dependent,Adenosine Triphosphatase,DNA-Dependent ATPase,DNA-Dependent Adenosinetriphosphatases,ATPase, DNA Dependent,Adenosinetriphosphatases, DNA-Dependent,DNA Dependent ATPase,DNA Dependent Adenosinetriphosphatases,Triphosphatase, Adenosine
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D015879	Myosin Subfragments	Parts of the myosin molecule resulting from cleavage by proteolytic enzymes (PAPAIN; TRYPSIN; or CHYMOTRYPSIN) at well-localized regions. Study of these isolated fragments helps to delineate the functional roles of different parts of myosin. Two of the most common subfragments are myosin S-1 and myosin S-2. S-1 contains the heads of the heavy chains plus the light chains and S-2 contains part of the double-stranded, alpha-helical, heavy chain tail (myosin rod).	Actomyosin Subfragments,Meromyosin Subfragments,Myosin Rod,Myosin S-1,Myosin S-2,ATPase, Actin-S1,Actin S1 ATPase,Actoheavy Meromyosin,Actomyosin Subfragment 1 ATPase,H-Meromyosin,Heavy Meromyosin,Heavy Meromyosin Subfragment-1,Heavy Meromyosin Subfragment-2,Light Meromyosin,Myosin Subfragment-1,Myosin Subfragment-2,ATPase, Actin S1,Actin-S1 ATPase,H Meromyosin,Heavy Meromyosin Subfragment 1,Heavy Meromyosin Subfragment 2,Meromyosin Subfragment-1, Heavy,Meromyosin Subfragment-2, Heavy,Meromyosin, Actoheavy,Meromyosin, Heavy,Meromyosin, Light,Myosin S 1,Myosin S 2,Myosin Subfragment 1,Myosin Subfragment 2,Subfragment-1, Heavy Meromyosin,Subfragment-1, Myosin,Subfragment-2, Heavy Meromyosin,Subfragment-2, Myosin,Subfragments, Actomyosin,Subfragments, Meromyosin,Subfragments, Myosin