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Nuclear Magnetic Resonance Spectroscopy for the Identification of Multiple Phosphorylations of Intrinsically Disordered Proteins
Published on: December 27, 2016
Distinct phosphorylation sites differentially influence facilitated transport of an NLS-protein and its subsequent
I Vancurova1, J Jochova-Rupes, W Lou
1Department of Biological Sciences, St. John's University, Jamaica, New York 11439, USA.
Abstract:
We measured the nuclear transport of radiolabeled fusion proteins consisting of variants of the Simian Virus 40 large T antigen's nuclear localization sequence region linked to beta-galactosidase, itself a cytoplasmic protein. We microinjected the fusion protein variants into the cytoplasm of living Xenopus oocytes or supplied them to the surface of oil-isolated oocyte nuclei via paired beads or cytoplasm. Presence of the cdc2 kinase site (124T) on the amino flank of the nuclear localization sequence (126PKKKRKV132) greatly enhances facilitated transport through the nuclear pore complex; additional presence of the casein kinase II site (112S) enhances subsequent intranuclear binding.
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