he CamShaft (amino acids 466-496) is a favorite resting spot of many of the original
cold-sensitive mutants as well as a raft of suppressors. Clearly, the data is jumping
up and down trying to tell us SOMEthing. Go to CamShaft=King
to see what the cryptic message might be! Involvement of helix 466-496
in myosin conformational state.
he G680V mutation has been the subject of a lot of our biochemical and genetic
analysis. As the first mutant to receive our full attention, it also represents a critical
test of the validity of our approach. In order to justify this work, we must confront
the question of whence cometh G680V suppressors
and are they just a bunch of 'noise' or is there a molecular message inscribed in their
identities and locations? Effects of G680V and its suppressors on
opening of 'back door' (= Pi release)
ur 'big picture' goal is to sketch out the conformations the motor adopts as it
goes through its cycle. We have now amassed enough suppressor data that we're starting
to be able to perceive mutant 'families'--groups that behave similarly (from a genetic
standpoint). To see how and why we think this is shining light on dark parts of the motor's
cycle, check out It's a Family Affair. Identifying
conformational states using suppressor 'families'.
ne of the more intriguing suppressors we have come across is E150K. This mighty suppressor is capable of restoring life to the N483S, Y494K, W501L and G691C mutations! Yet it lives on the surface of myosin out of the immediate neighborhood of the hapless mutations it revives. Wherein is the secret of E150K's marvelous powers?
erhaps the deepest, darkest mystery of myosin is its interactions with actin. While
absolutely critical to the motor function of myosin (since actin is the object gripped
and moved by the motor) our access to information about these states is fleeting and of
low resolution. Of course, genetic information can shine a bright light down these dark
tunnels; go to the Quivering Chin to see what's
up (or down, as the case may be...). Unanticipated conformational
re-arrangement of lower jaw (= lower 50K domain)
he Holy Grail of this whole enterprise is to sketch out conformations of the motor that
we have yet to observe through other methods. This is an ambitious goal, but I think we're
starting to achieve some success here. A recent rash of suppressor sightings is focusing
our attention at one position of the CamShaft. To see a place where the Whale Turns, check
out Tossin'
and Turnin' Analysis of M486 and the bending of the CamShaft
observed in the ADP.vanadate structure vs. other structures.
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