A subset of RAB proteins modulates PP2A phosphatase activity

A subset of RAB proteins modulates PP2A phosphatase activity

Protein phosphatase 2A (PP2A) is one of the most abundant serine-threonine phosphatases in mammalian cells. PP2A is a hetero-trimeric holoenzyme participating in a variety of physiological processes whose deregulation is often associated to cancer. The specificity and activity of this phosphatase is tightly modulated by a family of regulatory B subunits that dock the catalytic subunit to the su...

Crystal structure of the PP2A phosphatase activator: implications for its PP2A-specific PPIase activity.

PTPA, an essential and specific activator of protein phosphatase 2A (PP2A), functions as a peptidyl prolyl isomerase (PPIase). We present here the crystal structures of human PTPA and of the two yeast orthologs (Ypa1 and Ypa2), revealing an all alpha-helical protein fold that is radically different from other PPIases. The protein is organized into two domains separated by a groove lined by high...

A serine/threonine phosphatase, PP2A, controls autoimmunity

Geranylgeranylation of Rab proteins.

37 James, G. L., Goldstein, J. I,., Brown, M. S., Rawson, T. E., Somers, T. C., McDowell, R. S., Crowlcy, C. W., Lucas, B. K., Levinson, A. D. and Marsters, Jr., J. C. (1993) Science 260, 1937-1942 38 Cox, A. D., Garcia, A. M., Westwick, J. K., Kowalczyk, J. J., Lewis, M. D., Brenner, D. A. and Iler, C. J. (1994) J. Biol. Chem. 269, 19203-19206 39 Manne, V., Yan, N., Carlioni, J. M., Tuomari, A...

PP2A Phosphatase as a Regulator of ROS Signaling in Plants.

Reactive oxygen species (ROS) carry out vital functions in determining appropriate stress reactions in plants, but the molecular mechanisms underlying the sensing, signaling and response to ROS as signaling molecules are not yet fully understood. Recent studies have underscored the role of Protein Phosphatase 2A (PP2A) in ROS-dependent responses involved in light acclimation and pathogenesis re...