Two immunoglobulin-like domains of the Z-disc portion of titin interact in a conformation-dependent way with telethonin.
The giant muscle protein titin/connectin plays a crucial role in myofibrillogenesis as a molecular ruler for sarcomeric protein sorting. We describe here that the N-terminal titin immunoglobulin domains Z1 and Z2 interact specifically with telethonin in yeast two-hybrid analysis and protein binding assays. Immunofluorescence with antibodies against the N-terminal region of titin and telethonin detects both proteins at the Z-disc of human myotubes. Longer titin fragments, comprising a serine-proline-rich phosphorylation site and the next domain, do not interact. The interaction of telethonin with titin is therefore conformation-dependent, reflecting a possible phosphorylation regulation during myofibrillogenesis.
Mues
A
A
Structural Biology Division, European Molecular Biology Laboratory, Heidelberg, Germany.
van der Ven
P F
PF
Young
P
P
Fürst
D O
DO
Gautel
M
M
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D064211:Connectin; D006801:Humans; D007136:Immunoglobulins / Q000378:metabolism*; D008969:Molecular Sequence Data; D009124:Muscle Proteins / Q000378:metabolism*; D011487:Protein Conformation; D011494:Protein Kinases / Q000378:metabolism*; D011817:Rabbits; D012518:Sarcomeres / Q000378:metabolism; D013329:Structure-Activity Relationship
D064211:Connectin; D007136:Immunoglobulins; D009124:Muscle Proteins; C577292:TCAP protein, human; C577285:TTN protein, human; D011494:Protein Kinases