Identification of a Z-band associated protein complex involving KY, FLNC and IGFN1.
The KY protein underlies a form of muscular dystrophy in the mouse but its role in muscle remains elusive. Immunodetection of endogenous KY protein in C2C12-derived myotubes and expression of a recombinant form in neonatal cardiomyocytes indicated that KY is a Z-band associated protein. Moreover, characterization of a KY interacting protein fragment led to the identification of Igfn1 (Immunoglobulin-like and fibronectin type 3 domain containing 1). Igfn1 is a transcriptionally complex locus encoding many protein variants. A yeast two-hybrid screen identified the Z-band protein filamin C (FLNC) as an interacting partner. Consistent with this, expression of an IGFN1 recombinant fragment showed that the three N-terminal globular domains, common to at least five IGFN1 variants, are sufficient to provide Z-band targeting. Taken together, the yeast two-hybrid, biochemical and immunofluorescence data support the notion that KY, IGFN1 and FLNC are part of a Z-band associated protein complex likely to provide structural support to the skeletal muscle sarcomere.
Baker
Jane
J
MRC Harwell, Harwell OX11 0RD, UK.
Riley
Genna
G
Romero
M Rosario
MR
Haynes
Andrew R
AR
Hilton
Helen
H
Simon
Michelle
M
Hancock
John
J
Tateossian
Hilda
H
Ripoll
Vera M
VM
Blanco
Gonzalo
G
D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D002460:Cell Line; D003285:Contractile Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D064448:Filamins; D066298:In Vitro Techniques; D051379:Mice; D008840:Microfilament Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D046912:Multiprotein Complexes / Q000737:chemistry / Q000302:isolation & purification; D018485:Muscle Fibers, Skeletal / Q000737:chemistry; D009124:Muscle Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D018482:Muscle, Skeletal / Q000737:chemistry; D032383:Myocytes, Cardiac / Q000378:metabolism; D010447:Peptide Hydrolases; D025941:Protein Interaction Mapping; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D012518:Sarcomeres / Q000737:chemistry; D014018:Tissue Distribution; D020798:Two-Hybrid System Techniques
D002352:Carrier Proteins; D003285:Contractile Proteins; D017931:DNA Primers; D018076:DNA, Complementary; D064448:Filamins; D008840:Microfilament Proteins; D046912:Multiprotein Complexes; D009124:Muscle Proteins; D011994:Recombinant Proteins; C506764:KY protein, mouse; D010447:Peptide Hydrolases