Microinjection of recombinant O-GlcNAc transferase potentiates Xenopus oocytes M-phase entry.
In order to understand the importance of the cytosolic and nuclear-specific O-linked N-acetylglucosaminylation (O-GlcNAc) on cell cycle regulation, we recently reported that inhibition of O-GlcNAc transferase (OGT) delayed or blocked Xenopus laevis oocyte germinal vesicle breakdown (GVBD). Here, we show that increased levels of the long OGT isoform (ncOGT) accelerate X. laevis oocyte GVBD. A N-terminally truncated isoform (sOGT) with a similar in vitro catalytic activity towards a synthetic CKII-derived peptide had no effect, illustrating the important role played by the N-terminal tetratrico-peptide repeats. ncOGT microinjection in the oocytes increases both the speed and extent of O-GlcNAc addition, leads to a quicker activation of the MPF and MAPK pathways and finally results in a faster GVBD. Microinjection of anti-OGT antibodies leads to a delay of the GVBD kinetics. Our results hence demonstrate that OGT is a key molecule for the timely progression of the cell cycle.
Dehennaut
Vanessa
V
UMR-CNRS 8576, UGSF, USTL, IFR 147, 59655 Villeneuve d'Ascq, France.
Hanoulle
Xavier
X
Bodart
Jean-François
JF
Vilain
Jean-Pierre
JP
Michalski
Jean-Claude
JC
Landrieu
Isabelle
I
Lippens
Guy
G
Lefebvre
Tony
T
D000117:Acetylglucosamine / Q000378:metabolism*; D000818:Animals; D002455:Cell Division / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D008845:Microinjections; D017351:N-Acetylglucosaminyltransferases / Q000008:administration & dosage* / Q000235:genetics / Q000378:metabolism*; D009865:Oocytes / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D011994:Recombinant Proteins / Q000008:administration & dosage; D014982:Xenopus laevis
D011994:Recombinant Proteins; D017351:N-Acetylglucosaminyltransferases; C449880:O-GlcNAc transferase; D000117:Acetylglucosamine