Paraspeckles: paragons of functional aggregation.
Low-complexity proteins undergo phase separation in vitro, forming hydrogels or liquid droplets. Whether these form in vivo, and under what conditions, is still unclear. In this issue, Hennig et al. (2015. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201504117) show that formation of the paraspeckle, a nuclear body that regulates gene expression, requires low-complexity prion-like domains (PLDs) within paraspeckle proteins. The same proteins were shown to form hydrogels, shedding light on the role of "functional aggregation" in nuclear substructure.
Yale University, New Haven, CT 06511.
Edward
E
Courchaine
Yale University, New Haven, CT 06511 karla.neugebauer@yale.edu.
Karla M
KM
Neugebauer
D002467:Cell Nucleus / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000502:physiology*; D011328:Prions / Q000737:chemistry*; D016601:RNA-Binding Proteins / Q000737:chemistry*
D047908:Intracellular Signaling Peptides and Proteins; D011328:Prions; D016601:RNA-Binding Proteins