TY - JOUR
T1 - Myosin IIB is unconventionally conventional
AU - Rosenfeld, Steven S.
AU - Xing, Jun
AU - Chen, Li Qiong
AU - Sweeney, H. Lee
PY - 2003/7/25
Y1 - 2003/7/25
N2 - Members of the myosin II class of molecular motors have been referred to as "conventional," a term used to describe their ability to form thick filaments, their low duty ratio, the ability of individual motor-containing "heads" to operate independently of each other, and their rate-limiting phosphate release. These features ensure that those motors that have completed their power stroke dissociate rapidly enough to prevent them from interfering with those motors that are beginning theirs. However, in this study, we demonstrate that myosin IIB, a cytoplasmic myosin II particularly enriched in the central nervous system and cardiac tissue, has a number of features that it shares instead with "unconventional" myosin isoforms, including myosins V and VI. These include a high duty ratio, rate-limiting ADP release, and high ADP affinity. These features imply that myosin IIB serves a set of physiologic needs different from those served by its more conventional myosin II counterparts, and this work provides a plausible basis for explaining the physiologic role of this unconventionally conventional myosin.
AB - Members of the myosin II class of molecular motors have been referred to as "conventional," a term used to describe their ability to form thick filaments, their low duty ratio, the ability of individual motor-containing "heads" to operate independently of each other, and their rate-limiting phosphate release. These features ensure that those motors that have completed their power stroke dissociate rapidly enough to prevent them from interfering with those motors that are beginning theirs. However, in this study, we demonstrate that myosin IIB, a cytoplasmic myosin II particularly enriched in the central nervous system and cardiac tissue, has a number of features that it shares instead with "unconventional" myosin isoforms, including myosins V and VI. These include a high duty ratio, rate-limiting ADP release, and high ADP affinity. These features imply that myosin IIB serves a set of physiologic needs different from those served by its more conventional myosin II counterparts, and this work provides a plausible basis for explaining the physiologic role of this unconventionally conventional myosin.
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U2 - 10.1074/jbc.M302555200
DO - 10.1074/jbc.M302555200
M3 - Article
C2 - 12740390
AN - SCOPUS:0041845411
SN - 0021-9258
VL - 278
SP - 27449
EP - 27455
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 30
ER -