Isoform-specific differences in rapid nucleocytoplasmic shuttling cause distinct subcellular distributions of 14-3-3σ and 14-3-3ζ

• DOI: 10.1242/jcs.00990
• Publication Date: 2004-03-09T01:13:25Z
• Authors: Martijn J. van He...; Maarten Niemantsv...; Thomas Schmidt; Claude Backendorf; Herman P. Spaink
• Keywords: Nuclear export signal

Nucleocytoplasmic transport of proteins plays an important role in the regulation many cellular processes. Differences nucleocytoplasmic shuttling can provide a basis for isoform-specific biological functions members multigene families, like 14-3-3 protein family. Many organisms contain multiple isoforms, which play numerous processes, including signalling, cell cycle control and apoptosis. It is still unclear whether these isoforms have specialised this specialisation based on ligand binding, expression or specific localisation. Therefore, we studied subcellular distribution sigma zeta vivo various mammalian types using yellow fluorescent fusions antibodies. was mainly localised cytoplasm only low levels were present nucleus, whereas found at relatively higher nucleus. Fluorescence recovery after photobleaching (FRAP) experiments indicated that rapidly shuttle out nucleus through active distinct distributions are caused by differences nuclear export. had 1.7x export rate constant than zeta, while import constants equal. The exported from least part Crm1-dependent, leptomycin B-sensitive mechanism. study likely to reflect molecular specialisation.