Distinct pseudokinase domain conformations underlie divergent activation mechanisms among vertebrate MLKL orthologues
Katherine A Davies, Cheree Fitzgibbon, Samuel N Young, Sarah E Garnish, Wayland Yeung, Diane Coursier, Richard W Birkinshaw, Jarrod J Sandow, Wil IL Lehmann, Lung-Yu Liang, Isabelle S Lucet, James D Chalmers, Wayne M Patrick, Natarajan Kannan, Emma J Petrie, Peter E Czabotar, James M Murphy
NATURE COMMUNICATIONS | NATURE PUBLISHING GROUP | Published : 2020
The MLKL pseudokinase is the terminal effector in the necroptosis cell death pathway. Phosphorylation by its upstream regulator, RIPK3, triggers MLKL's conversion from a dormant cytoplasmic protein into oligomers that translocate to, and permeabilize, the plasma membrane to kill cells. The precise mechanisms underlying these processes are incompletely understood, and were proposed to differ between mouse and human cells. Here, we examine the divergence of activation mechanisms among nine vertebrate MLKL orthologues, revealing remarkable specificity of mouse and human RIPK3 for MLKL orthologues. Pig MLKL can restore necroptotic signaling in human cells; while horse and pig, but not rat, MLKL ..View full abstract
Awarded by National Health and Medical Research Council
Awarded by NIH
We thank staff at the Australian Synchrotron MX beamline for assistance with data collection. This research was undertaken in part using the MX2 crystallography beamline at the Australian Synchrotron, Victoria, Australia, and made use of the ACRF Detector. We gratefully acknowledge Clive Stone (Te Iwi o Ngatiwai) for enabling the tuatara MLKL sequence to be shared ahead of its publication. We acknowledge scholarship support for K.A.D. and S.E.G. (Australian Government Research Training Program Stipend Scholarships), L.-Y.L. (Melbourne Research Scholarship) and K.A.D. (AINSE PGRA scholarship). We are grateful to the National Health and Medical Research Council for fellowship (PEC, 1079700; JMM, 1105754, 1172929), grant (1057905; 1124735) and infrastructure (IRIISS 9000587) support; Australian Cancer Research Foundation; and the Victorian Government Operational Infrastructure Support scheme. Funding for N.K. from NIH (5R01GM114409) is acknowledged.