title: Novel function of beta-arrestin2 in the nucleus of mature spermatozoa.
abstract: A growing number of proteins originally found in endocytic structures of the plasma membrane appear to be able to traffic into the nucleus, but the cellular function of this translocation remains unclear. We have found that beta-arrestin2, which typically shows a cytoplasmic localization owing to constitutive nuclear export, appears in the nucleus after stimulation of the G-protein-coupled odorant receptor hOR17-4. In the nucleus, beta-arrestin2 was involved in transcriptional regulation as shown by a Gal4-based transactivation assay. Moreover, we discovered that beta-arrestin2 and hOR17-4, a receptor known to have a role in sperm-egg communication, colocalize in the midpiece of mature human spermatozoa. Stimulation of hOR17-4 in spermatozoa induced PKA-dependent translocation of beta-arrestin2 to the nucleus and nuclear accumulation of phosphorylated MAPKs. Analysis of the interaction partners of beta-arrestin2 indicates that odorant receptor signaling in spermatozoa may be important for the regulation of gene expression during the early processes of fertilization.
authors.affiliation: Department of Cell Physiology, Ruhr-Universitaet Bochum, Universitaetsstr. 150, 44780 Bochum, Germany. eva.neuhaus@rub.de
authors.forename: Eva M
authors.initials: EM
authors.lastname: Neuhaus
authors.forename: Anastasia
authors.initials: A
authors.lastname: Mashukova
authors.forename: Jon
authors.initials: J
authors.lastname: Barbour
authors.forename: Dirk
authors.initials: D
authors.lastname: Wolters
authors.forename: Hanns
authors.initials: H
authors.lastname: Hatt
mesh_terms: D000447:Aldehydes / Q000378:metabolism; D019390:Arrestins / Q000378:metabolism*; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004789:Enzyme Activation; D006801:Humans; D008024:Ligands; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D018035:Receptors, Odorant / Q000378:metabolism; D029589:Seminal Plasma Proteins / Q000378:metabolism; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D000071557:beta-Arrestins
chemical_list: D000447:Aldehydes; D019390:Arrestins; D008024:Ligands; C473192:OR1D2 protein, human; D018035:Receptors, Odorant; D029589:Seminal Plasma Proteins; D000071557:beta-Arrestins; D017868:Cyclic AMP-Dependent Protein Kinases; D020928:Mitogen-Activated Protein Kinases; C473193:bourgeonal