RNA-binding protein RBM8A (Y14) and MAGOH localize to centrosome in human A549 cells.
RBM8A (Y14) is carrying RNA-binding motif and forms the tight heterodimer with MAGOH. The heterodimer is known to be a member of exon junction complex on exporting mRNA and is required for mRNA metabolisms such as splicing, mRNA export and nonsense-mediated mRNA decay. Almost all RBM8A-MAGOH complexes localize in nucleoplasm and shuttle between nuclei and cytoplasm for RNA metabolism. Recently, the abnormality of G2/M transition and aberrant centrosome regulation in RBM8A- or MAGOH-deficient cells has been reported. These results prompt us to the reevaluation of the localization of RBM8A-MAGOH in human cells. Interestingly, our immunostaining experiments showed the localization of these proteins in centrosome in addition to nuclei. Furthermore, the transiently expressed eYFP-tagged RBM8A and Flag-tagged MAGOH also co-localized with centrosome signals. In addition, the proximity ligation in situ assay was performed to detect the complex formation in centrosome. Our experiments clearly showed that Myc-tagged RBM8A and Flag-tagged MAGOH formed a complex in centrosome. GFP-tagged PLK1 also co-localized with Myc-RBM8A. Our results show that RBM8A-MAGOH complex is required for M-phase progression via direct localization to centrosome rather than indirect effect.
Medical Research Institute, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Kahoku, 920-0293, Japan, ishigaki@kanazawa-med.ac.jp.
Yasuhito
Y
Ishigaki
Yuka
Y
Nakamura
Takanori
T
Tatsuno
Mitsumasa
M
Hashimoto
Kuniyoshi
K
Iwabuchi
Naohisa
N
Tomosugi
D021581:Active Transport, Cell Nucleus / Q000235:genetics; D002455:Cell Division / Q000235:genetics; D002460:Cell Line; D002467:Cell Nucleus / Q000235:genetics; D018385:Centrosome / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics / Q000493:pharmacokinetics*; D012333:RNA, Messenger / Q000235:genetics; D016601:RNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics / Q000493:pharmacokinetics*
C491494:MAGOH protein, human; D009687:Nuclear Proteins; C406243:RBM8A protein, human; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D049452:Green Fluorescent Proteins