The N-terminal sequence of paratropomyosin binding fragments from beta-connectin.
In order to clarify the position where paratropomyosin binds to connectin in the A-I junction region of a sarcomere, chicken beta-connectin was digested by Staphylococcus aureus V8 protease under denaturing conditions and the digested peptides were electrophoretically separated. Five peptides, 150-kDa, 100-kDa, 70-kDa, and 43-kDa fragments, were simultaneously detected by biotinylated paratropomyosin and an anti-connectin monoclonal antibody. The N-terminal sequence of the 43-kDa fragment was found to be YQFRVYAVNK, similar to the sequence of 7556-7565 amino acids in the I51 fibronectin type 3 domain that was located at the A-I junction region of human cardiac titin/connectin. Therefore, we propose that paratropomyosin binds to the 43-kDa fragment from beta-connectin at the A-I junction region in both living muscle and in muscle immediately postmortem, and the N-terminus of the 43-kDa fragment is localized in the I51 domain.
Yamanoue
Minoru
M
Faculty of Agriculture, Kobe University, Kobe, Hyogo 657-8501, Japan. yamanoue@kobe-u.ac.jp
Ueda
Shuji
S
Ohashi
Akiko
A
Yoshimura
Yumi
Y
Norioka
Shigemi
S
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry; D001710:Biotin / Q000737:chemistry; D002645:Chickens; D064211:Connectin; D015180:Electrophoresis, Gel, Two-Dimensional; D005353:Fibronectins / Q000737:chemistry / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009124:Muscle Proteins / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D011485:Protein Binding; D011494:Protein Kinases / Q000737:chemistry*; D017434:Protein Structure, Tertiary / Q000235:genetics; D012697:Serine Endopeptidases / Q000378:metabolism; D013211:Staphylococcus aureus / Q000201:enzymology; D014335:Tropomyosin / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
D000911:Antibodies, Monoclonal; D064211:Connectin; D005353:Fibronectins; D009124:Muscle Proteins; D010446:Peptide Fragments; C577285:TTN protein, human; D014335:Tropomyosin; D001710:Biotin; D011494:Protein Kinases; D012697:Serine Endopeptidases