Multiplicity of abnormal dystrophin in Becker muscular dystrophy. A Becker muscular dystrophy gene frequently produced two smaller sizes of dystrophin.
Dystrophin is a muscle cytoskeletal protein with a molecular mass (MM) of approximately 420 kDa and an isoelectric point (pI) of approximately 5.5, which is abnormal in size and/or abundance in Becker muscular dystrophy (BMD). We investigated the abnormality of dystrophin molecule in muscles biopsied from 23 BMD patients using the two-dimensional gel electrophoresis (TDGE). We found 7 protein spots which reacted specifically with the monoclonal anti-dystrophin antibody (mAb) A1C raised against N-terminal domain of the normal dystrophin. These spots were focused on the two-dimensional gel at the same position as the normal dystrophin (#1), at the position with MM approximately 480 kDa/pI approximately 5.35 (#2), the position with MM approximately 400-330 kDa/pI approximately 5.51-5.47 (#3), the position with MM approximately 300 kDa/pI approximately 5.4 (#4), the position with MM approximately 235-250 kDa/pI approximately 5.53-5.5 (#5), the position with MM approximately 165 kDa/pI approximately 6.0 (#6), and the position with MM approximately 160 kDa/pI approximately 5.75 (#7). These spots were classified into five patterns in individuals, that is, #1 alone in 3 patients, #3 alone in 1, the combination of #3 and 5 in 17, the combination of #1, 3 and 5 in 1 and the combination of #1, 2, 4, 6 and 7 in 1. The combination of #3 and 5 was observed in 17 of 23 patients (75%).(ABSTRACT TRUNCATED AT 250 WORDS)
Hori
S
S
Department of Molecular and Cellular Neurobiology, Tokyo Metropolitan Institute for Neuroscience, Japan.
Ohtani
S
S
Shimizu
T
T
Ibi
T
T
Sahashi
K
K
Nonaka
I
I
Miyamoto
K
K
Tanabe
H
H
D000293:Adolescent; D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology; D015153:Blotting, Western; D002648:Child; D016189:Dystrophin / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D006801:Humans; D007525:Isoelectric Focusing; D008297:Male; D008875:Middle Aged; D008970:Molecular Weight; D009124:Muscle Proteins / Q000378:metabolism; D009135:Muscular Diseases / Q000378:metabolism; D009136:Muscular Dystrophies / Q000235:genetics / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D016189:Dystrophin; D009124:Muscle Proteins