References
PMID:16944320
The enzymatic activity of GSK3 is enhanced by phosphorylation of tyrosine-216 in GSK3b
GSK3 is considered to be largely a cytosolic enzyme, but it is also associated with, or internalized in, subcellular compartments such as the nucleus, mitochondria, and growth cones
PMID:9832503
GSK3 is predominatly cytoplasmic during G1 phase of the celle cycle, but a significant fraction enters the nucleus during S phase, promoting its ability to phosphorylate cyclin D1 in the nucleus
Phosphorylation of cyclin D1 on a single threonine residue near the carboxyl terminus (Thr-286) positively regulates proteasomal degradation of D1
GSK3 phosphorylates cyclin D1 specifically on Thr-286, thereby triggering rapid cyclin D1 turnover.
PMID:14663202
GSK3B is highly activated in nuclei and mitochondria.