J. Cabezasherrera et al., GLYCOSYLATION OF ACETYLCHOLINESTERASE FORMS IN MICROSOMAL-MEMBRANES FROM NORMAL AND DYSTROPHIC LAMA2(DY) MOUSE MUSCLE, Journal of neurochemistry, 69(5), 1997, pp. 1964-1974
The distribution and glycosylation of acetylcholinesterase (AChE) form
s in vesicles derived from sarcoplasmic reticulum of normal muscle (NM
V) were investigated and compared with those from dystrophic muscle ve
sicles (DMV). AChE activity was similar in NMV and DMV. Most of the AC
hE in NMV and half in DMV were released with Triton X-100. Asymmetric
(A(12)) and globular hydrophilic and amphiphilic (G(4)(H), G(4)(A), G(
2)(A), and G(1)(A)) AChE species occurred in NMV and DMV, the lighter
forms being predominant. The percentage of G(4)(H) and G(4)(A) decreas
ed in DMV. A fraction of the AChE that could not be extracted with det
ergent was detached with collagenase. Most of the detergent-released A
(12) AChE from NMV and nearly half in DMV failed to bind to Ricinus co
mmunis agglutinin (RCA-I), Conversely, the collagenase-detached isofor
ms bound to RCA, revealing that asymmetric AChE associated with intern
al membranes or basal lamina differed in glycosylation. Moreover, near
ly half of G(4)(A) AChE in DMV and a few in NMV bound to RCA. Most of
the RCA-unreactive G(4)(A) forms in NMV come from sarcolemma. The resu
lts indicate that dystrophy induces minor changes in the distribution
and glycosylation of AChE forms in internal membranes of muscle.