Paper Chase is a research database designed to offer abstracts of research articles published in journals that have a highly rated impact factor as determined by ISI Impact Factor and PageRank. Abstracts are organized by date, with the most recently published papers listed first. 

Paper Chase

Calcineurin determines toxic versus beneficial responses to α-synuclein.

Proc. Natl. Acad. Sci. U.S.A.. Aug 26, 2014;111(34):E3544-52.
Caraveo G, Auluck PK, Whitesell L, Chung CY, Baru V, Mosharov EV, Yan X, Ben-Johny M, Soste M, Picotti P, Kim H, Caldwell KA, Caldwell GA, Sulzer D, Yue DT, Lindquist S.

Whitehead Institute for Biomedical Research, Cambridge, MA 02142; Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139; lindquist@wi.mit.edu.

Abstract:

Calcineurin (CN) is a highly conserved Ca(2+)-calmodulin (CaM)-dependent phosphatase that senses Ca(2+) concentrations and transduces that information into cellular responses. Ca(2+) homeostasis is disrupted by α-synuclein (α-syn), a small lipid binding protein whose misfolding and accumulation is a pathological hallmark of several neurodegenerative diseases. We report that α-syn, from yeast to neurons, leads to sustained highly elevated levels of cytoplasmic Ca(2+), thereby activating a CaM-CN cascade that engages substrates that result in toxicity. Surprisingly, complete inhibition of CN also results in toxicity. Limiting the availability of CaM shifts CN's spectrum of substrates toward protective pathways. Modulating CN or CN's substrates with highly selective genetic and pharmacological tools (FK506) does the same. FK506 crosses the blood brain barrier, is well tolerated in humans, and is active in neurons and glia. Thus, a tunable response to CN, which has been conserved for a billion years, can be targeted to rebalance the phosphatase's activities from toxic toward beneficial substrates. These findings have immediate therapeutic implications for synucleinopathies.