The epsilon subunit confers fast channel gating on multiple classes of acetylcholine receptors.
During vertebrate skeletal muscle development, multiple forms of long-open-time (slow-type) ACh receptor channels are replaced by at least two different types of short-open-time (fast-type) ACh receptors. Expression of ACh receptors in Xenopus oocytes indicates that the substitution of an epsilon subunit for a gamma subunit may account for both types of fast-gated channel types in adult muscle. Unlike the various forms of the embryonic receptor, in which functional diversity is achieved through alterations in subunit composition, the two major fast-gated forms expressed in oocytes have identical subunit composition. These findings provide a structural basis for both types of short-open-time ACh receptor types found in adult muscle.
Camacho
P
P
Department of Neurobiology and Behavior, SUNY, Stony Brook 11794.
Liu
Y
Y
Mandel
G
G
Brehm
P
P
D000818:Animals; D004553:Electric Conductivity; D005260:Female; D015870:Gene Expression; D015640:Ion Channel Gating / Q000502:physiology*; D007473:Ion Channels / Q000502:physiology*; D007700:Kinetics; D051379:Mice; D009121:Muscle Denervation; D024510:Muscle Development; D009132:Muscles / Q000737:chemistry / Q000196:embryology; D009865:Oocytes / Q000378:metabolism; D012313:RNA / Q000235:genetics; D018075:RNA, Complementary; D011950:Receptors, Cholinergic / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D013329:Structure-Activity Relationship; D014162:Transfection; D014982:Xenopus laevis
D007473:Ion Channels; D018075:RNA, Complementary; D011950:Receptors, Cholinergic; D012313:RNA