Myosin I mutants with only 1% of wild-type actin-activated MgATPase activity retain essential in vivo function(s)
2001
Liu, X. | Osherov, N. | Yamashita, R. | Brzeska, H. | Korn, E.D. | May, G.S.
The single class I myosin (MYOA) of Aspergillus nidulans is essential for hyphal growth. It is generally assumed that the functions of all myosins depend on their actin-activated MgATPase activity. Here we show that MYOA mutants with no more than 1% of the actin-activated MgATPase activity of wild-type MYOA in vitro and no detectable in vitro motility activity can support fungal cell growth, albeit with a delay in germination time and a reduction in hyphal elongation. From these and other data, we conclude that the essential role(s) of myosin I in A. nidulans is probably structural, requiring little, if any, actin-activated MgATPase or motor activity, which have long been considered the defining characteristics of the myosin family.
显示更多 [+] 显示较少 [-]