Phosphorylation can modulate the association of different sets of RNA binding proteins with the Vg1 localization signal RNA.
As assayed by both in vivo and in vitro UV-crosslinking techniques, four RNA binding proteins, with apparent molecular weight of 56, 54, 42, and 40 kilodaltons, associated specifically with the Xenopus Vg1 mRNA localization signal (LS) RNA. The 56 and 54 kD proteins were assigned as the masking proteins described previously, on the basis of their thermal stability and the effect of phosphorylation on RNA binding activity. The 42 and 40 kD proteins associated with the LS RNA at a lower extract concentration than the masking proteins did in vitro. Dephosphorylation will eliminate the RNA binding activities of all four proteins. However, either raising the extract concentration or phosphorylating the extract by the catalytic domain of protein kinase A had opposite effects on the crosslinking efficiencies of these two sets of RNA binding proteins. Phosphorylation might regulate this protein exchange process in vitro.
Chen
S M
SM
Institute of Biochemistry, College of Life Sciences, National Yang-Ming University, Taipei, Taiwan, Republic of China.
Su
C
C
Yang
U C
UC
D000818:Animals; D016764:Cell Polarity; D003432:Cross-Linking Reagents; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D005260:Female; D006023:Glycoproteins / Q000235:genetics*; D066298:In Vitro Techniques; D008970:Molecular Weight; D010766:Phosphorylation; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D016212:Transforming Growth Factor beta; D014466:Ultraviolet Rays; D029867:Xenopus Proteins; D014982:Xenopus laevis
D003432:Cross-Linking Reagents; C513103:GDF1 protein, Xenopus; D006023:Glycoproteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D016212:Transforming Growth Factor beta; D029867:Xenopus Proteins; D017868:Cyclic AMP-Dependent Protein Kinases