MYC-Associated Factor MAX is a Regulator of the Circadian Clock.

International journal of molecular sciences (2020-04-01)
Olga Blaževitš, Nityanand Bolshette, Donatella Vecchio, Ana Guijarro, Ottavio Croci, Stefano Campaner, Benedetto Grimaldi
ABSTRACT

The circadian transcriptional network is based on a competition between transcriptional activator and repressor complexes regulating the rhythmic expression of clock-controlled genes. We show here that the MYC-associated factor X, MAX, plays a repressive role in this network and operates through a MYC-independent binding to E-box-containing regulatory regions within the promoters of circadian BMAL1 targets. We further show that this "clock" function of MAX is required for maintaining a proper circadian rhythm and that MAX and BMAL1 contribute to two temporally alternating transcriptional complexes on clock-regulated promoters. We also identified MAX network transcriptional repressor, MNT, as a fundamental partner of MAX-mediated circadian regulation. Collectively, our data indicate that MAX regulates clock gene expression and contributes to keeping the balance between positive and negative elements of the molecular clock machinery.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Dulbecco′s Phosphate Buffered Saline, Modified, without calcium chloride and magnesium chloride, liquid, sterile-filtered, suitable for cell culture
Sigma-Aldrich
Penicillin-Streptomycin, Solution stabilized, with 10,000 units penicillin and 10 mg streptomycin/mL, 0.1 μm filtered, BioReagent, suitable for cell culture
Sigma-Aldrich
Insulin solution human, sterile-filtered, BioXtra, suitable for cell culture
Sigma-Aldrich
Formaldehyde solution, for molecular biology, 36.5-38% in H2O
Sigma-Aldrich
Puromycin dihydrochloride from Streptomyces alboniger, powder, BioReagent, suitable for cell culture
Sigma-Aldrich
hEGF, EGF, recombinant, expressed in E. coli, lyophilized powder, suitable for cell culture
Sigma-Aldrich
Horse Serum, Donor herd, USA origin, sterile-filtered, suitable for cell culture, suitable for hybridoma
Sigma-Aldrich
Hydrocortisone solution, 50 μM, sterile-filtered, BioXtra, suitable for cell culture
SAFC
Ham′s Nutrient Mixture F12, liquid
Sigma-Aldrich
Medium 199, Modified, with Earle′s salts, without L-glutamine, sodium bicarbonate, and phenol red, powder, suitable for cell culture