CRY1-CBS binding regulates circadian clock function and metabolism

AbstractCircadian disruption influences metabolic health. Metabolism modulates circadian function. However, the mechanisms coupling circadian rhythms and metabolism remain poorly understood. Here we report that Cystathionine β-synthase (CBS), a central enzyme in one-carbon metabolism, functionally interacts with the core circadian protein Cryptochrome1 (CRY1). In cells, CBS augments CRY1 mediated repression of the CLOCK/BMAL1 complex and shortens circadian period. Notably, we find that mutant CBS-I278T protein, the most common cause of homocystinuria, does not bind CRY1 or regulate its repressor activity. Transgenic CbsZn/Zn mice, while maintaining circadian locomotor activity period, exhibit reduced circadian power and increased expression of E-BOX outputs. CBS function is reciprocally influenced by CRY1 binding. CRY1 modulates enzymatic activity of the CBS. Liver extracts from Cry1−/− mice show reduced CBS activity that normalizes after the addition of exogenous wild type (WT) CRY1. Metabolomic analysis of WT, CbsZn/Zn, Cry1−/−, and Cry2−/− samples highlights the metabolic importance of endogenous CRY1. We observed temporal variation in one-carbon and transsulfuration pathways attributable to CRY1 induced CBS activation. CBS-CRY1 binding provides a post-translational switch to modulate cellular circadian physiology and metabolic control.

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Disrupted-in-schizophrenia 1 enhances the quality of circadian rhythm by stabilizing BMAL1

Translational Psychiatry ◽

10.1038/s41398-021-01212-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Su Been Lee ◽

Jihyun Park ◽

Yongdo Kwak ◽

Young-Un Park ◽

Truong Thi My Nhung ◽

...

Keyword(s):

Circadian Rhythm ◽

Mental Disorders ◽

Circadian System ◽

Circadian Genes ◽

Protein Levels ◽

The Core ◽

E Box ◽

Neuronal Proliferation ◽

Circadian Physiology

AbstractDisrupted-in-schizophrenia 1 (DISC1) is a scaffold protein that has been implicated in multiple mental disorders. DISC1 is known to regulate neuronal proliferation, signaling, and intracellular calcium homeostasis, as well as neurodevelopment. Although DISC1 was linked to sleep-associated behaviors, whether DISC1 functions in the circadian rhythm has not been determined yet. In this work, we revealed that Disc1 expression exhibits daily oscillating pattern and is regulated by binding of circadian locomotor output cycles kaput (CLOCK) and Brain and muscle Arnt-like protein-1 (BMAL1) heterodimer to E-box sequences in its promoter. Interestingly, Disc1 deficiency increases the ubiquitination of BMAL1 and de-stabilizes it, thereby reducing its protein levels. DISC1 inhibits the activity of GSK3β, which promotes BMAL1 ubiquitination, suggesting that DISC1 regulates BMAL1 stability by inhibiting its ubiquitination. Moreover, Disc1-deficient cells and mice show reduced expression of other circadian genes. Finally, Disc1-LI (Disc1 knockout) mice exhibit damped circadian physiology and behaviors. Collectively, these findings demonstrate that the oscillation of DISC1 expression is under the control of CLOCK and BMAL1, and that DISC1 contributes to the core circadian system by regulating BMAL1 stability.

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Translational control of one-carbon metabolism underpins ribosomal protein phenotypes in cell division and longevity

eLife ◽

10.7554/elife.53127 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 4

Author(s):

Nairita Maitra ◽

Chong He ◽

Heidi M Blank ◽

Mitsuhiro Tsuchiya ◽

Birgit Schilling ◽

...

Keyword(s):

Carbon Metabolism ◽

Translational Control ◽

Generation Time ◽

Ribosomal Proteins ◽

Deletion Mutants ◽

Wild Type ◽

Data Link ◽

One Carbon Metabolism ◽

Serine Metabolism ◽

Standing Problem

A long-standing problem is how cells that lack one of the highly similar ribosomal proteins (RPs) often display distinct phenotypes. Yeast and other organisms live longer when they lack specific ribosomal proteins, especially of the large 60S subunit of the ribosome. However, longevity is neither associated with the generation time of RP deletion mutants nor with bulk inhibition of protein synthesis. Here, we queried actively dividing RP mutants through the cell cycle. Our data link transcriptional, translational, and metabolic changes to phenotypes associated with the loss of paralogous RPs. We uncovered translational control of transcripts encoding enzymes of methionine and serine metabolism, which are part of one-carbon (1C) pathways. Cells lacking Rpl22Ap, which are long-lived, have lower levels of metabolites associated with 1C metabolism. Loss of 1C enzymes increased the longevity of wild type cells. 1C pathways exist in all organisms and targeting the relevant enzymes could represent longevity interventions.

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Formate can differentiate between hyperhomocysteinemia due to impaired remethylation and impaired transsulfuration

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00345.2011 ◽

2012 ◽

Vol 302 (1) ◽

pp. E61-E67 ◽

Cited By ~ 25

Author(s):

Simon G. Lamarre ◽

Anne M. Molloy ◽

Stacey N. Reinke ◽

Brian D. Sykes ◽

Margaret E. Brosnan ◽

...

Keyword(s):

Carbon Metabolism ◽

Folate Metabolism ◽

Methionine Synthase ◽

Vitamin B ◽

Metabolomic Analysis ◽

Elevated Plasma ◽

H Nmr ◽

Transsulfuration Pathway ◽

One Carbon Metabolism ◽

The One

Formate can differentiate between hyperhomocysteinemia due to impaired remethylation and impaired transsulfuration. Am J Physiol Endocrinol Metab 301: E000–E000, 2011. First published September 20, 2011; 10.1152/ajpendo.00345.2011.—We carried out a1H-NMR metabolomic analysis of sera from vitamin B12-deficient rats. In addition to the expected increases in methylmalonate and homocysteine (Hcy), we observed an approximately sevenfold increase in formate levels, from 64 μM in control rats to 402 μM in vitamin B12-deficient rats. Urinary formate was also elevated. This elevation of formate could be attributed to impaired one-carbon metabolism since formate is assimilated into the one-carbon pool by incorporation into 10-formyl-THF via the enzyme 10-formyl-THF synthase. Both plasma and urinary formate were also increased in folate-deficient rats. Hcy was elevated in both the vitamin B12- and folate-deficient rats. Although plasma Hcy was also elevated, plasma formate was unaffected in vitamin B6-deficient rats (impaired transsulfuration pathway). These results were in accord with a mathematical model of folate metabolism, which predicted that reduction in methionine synthase activity would cause increased formate levels, whereas reduced cystathionine β-synthase activity would not. Our data indicate that formate provides a novel window into cellular folate metabolism, that elevated formate can be a useful indicator of deranged one-carbon metabolism and can be used to discriminate between the hyperhomocysteinemia caused by defects in the remethylation and transsulfuration pathways.

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Genetic Variation: Impact on Folate (and Choline) Bioefficacy

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000040 ◽

2010 ◽

Vol 80 (45) ◽

pp. 319-329 ◽

Cited By ~ 9

Author(s):

Allyson A. West ◽

Marie A. Caudill

Keyword(s):

Carbon Metabolism ◽

Genetic Variants ◽

Plasma Homocysteine ◽

Water Soluble ◽

Gene Interactions ◽

Dietary Folate ◽

Methyl Donors ◽

Common Genetic Variants ◽

One Carbon Metabolism ◽

The Impact

Folate and choline are water-soluble micronutrients that serve as methyl donors in the conversion of homocysteine to methionine. Inadequacy of these nutrients can disturb one-carbon metabolism as evidenced by alterations in circulating folate and/or plasma homocysteine. Among common genetic variants that reside in genes regulating folate absorptive and metabolic processes, homozygosity for the MTHFR 677C > T variant has consistently been shown to have robust effects on status markers. This paper will review the impact of genetic variants in folate-metabolizing genes on folate and choline bioefficacy. Nutrient-gene and gene-gene interactions will be considered along with the need to account for these genetic variants when updating dietary folate and choline recommendations.

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