Which of the following statements about dynein heavy chains is TRUE?
Dynein heavy chains define motor identity through massive size and AAA ATPase ring arrangement unique among cytoskeletal motors distinguishable from kinesin and myosin smallest motors. Each 530 kDa heavy chain encodes six AAA plus repeats arranged in asymmetric ring with seventh pseudo AAA domain closing structure. AAA1 through AAA4 contain P loop Walker A motifs capable of nucleotide binding AAA1 major catalytic site hydrolyzing ATP for movement AAA2 through AAA4 bind ATP regulatory maintaining ring closure and coordinating allostery. AAA5 AAA6 structural no nucleotide hydrolysis. Linker arch
Ref: Roberts et al., Cell 2013 – Dynein heavy chain has ATPase domains within AAA+ ring true statement architecture.
