Nuclear localization of the phosphatidylserine receptor protein via multiple nuclear localization signals.
The interaction between phosphatidylserine and its receptor on phagocytic cells plays a critical role in the clearance of apoptotic bodies under normal physiological condition. A specific receptor for phosphatidylserine (PSR) has recently been identified by phage display and shown to mediate phosphatidylserine dependent phagocytosis. Here we show that the protein encoded by the PSR cDNA is localized in the nuclei through multiple nuclear localization signals. First, a fusion between PSR and GFP is localized in the nuclei of transfected cells, suggesting that PSR have intrinsic nuclear localization capability. Indeed, affinity-purified anti-PSR antibodies identified a 47 kDa protein species in cells transfected with untagged PSR and localized this protein in the nuclei by immunofluorescent confocal microscopy. In NIH3T3 cells, which express endogenous PSR mRNA, a similar 47 kDa species was detected and localized in the nuclei. Finally, multiple nuclear localization signals were identified in PSR sequence, each capable of targeting GFP to the nuclei. Together, these results suggest that PSR may serve a dual role both on the cell surface and in the nuclei.
Cui
Ping
P
Institute of Pharmacology, State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua Institutes of Biomedical Sciences, Tsinghua University, Beijing, China.
Qin
Baoming
B
Liu
Nan
N
Pan
Guangjin
G
Pei
Duanqing
D
D000230:Adenocarcinoma / Q000473:pathology; D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D004285:Dogs; D004926:Escherichia coli / Q000235:genetics; D005455:Fluorescent Antibody Technique; D049452:Green Fluorescent Proteins; D006367:HeLa Cells; D006801:Humans; D056484:Jumonji Domain-Containing Histone Demethylases; D007668:Kidney / Q000166:cytology; D008164:Luminescent Proteins / Q000378:metabolism; D008297:Male; D051379:Mice; D008970:Molecular Weight; D041681:NIH 3T3 Cells; D019913:Nuclear Localization Signals; D010718:Phosphatidylserines / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D017384:Sequence Deletion; D015398:Signal Transduction
D008164:Luminescent Proteins; D019913:Nuclear Localization Signals; D010718:Phosphatidylserines; C498708:Ptdsr protein, mouse; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; C408123:phosphatidylserine receptor; D049452:Green Fluorescent Proteins; C498707:JMJD6 protein, human; D056484:Jumonji Domain-Containing Histone Demethylases