Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.5.1.3 (
dihydrofolate reductase
)
5,819
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The oncoprotein cyclin D1 binds to and activates
cyclin-dependent kinase 4
(
cdk4
), whose activity is inhibited by p16INK4, the product of the putative tumor suppressor gene MTS1. Cyclin D1 controls the timing of S phase onset in mammalian cells. We show that cyclin D1 acts as a positive regulator of the transcription factor E2F. In particular, cyclin D1 overexpression leads to the activation of the
dihydrofolate reductase
(
DHFR
) gene promoter. Activation depends on the E2F binding site in the
DHFR
promoter, known to mediate its activation at the G1/S transition in vivo. Cyclin D1 can also activate the adenovirus E2 promoter via E2F. Both promoters are repressed by p16INK4 and this repression can be released by overexpression of
cdk4
. The data reported here support a direct role for cyclin D1 and its associated kinase in cell cycle regulation of E2F activity and S phase-specific gene expression. In addition, we show that both E2F sites bind complexes containing the retinoblastoma protein (pRB) and that in RB-deficient cell lines overexpression of cyclin D1 fails to activate E2F-dependent transcription, indicating that pRB may be involved in promoter activation.
...
PMID:Activation of the E2F transcription factor by cyclin D1 is blocked by p16INK4, the product of the putative tumor suppressor gene MTS1. 797 Jul 7