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Genetics and genomics of exposure to high altitude
Published in Andrew M. Luks, Philip N. Ainslie, Justin S. Lawley, Robert C. Roach, Tatum S. Simonson, Ward, Milledge and West's High Altitude Medicine and Physiology, 2021
Andrew M. Luks, Philip N. Ainslie, Justin S. Lawley, Robert C. Roach, Tatum S. Simonson
Putatively adaptive copies of the THRB gene region, as well as PPARA and EPAS1 identified in Tibetans (Simonson et al. 2010), show relationships with hemoglobin concentration in Amhara Ethiopians (Scheinfeldt et al. 2012). EDNRB (endothelial receptor B), previously reported as a top selection candidate in Andeans (Bigham et al. 2010), is also reported in Amhara Ethiopians, and knockdown of this gene increases hypoxia tolerance in mice (Udpa et al. 2014). The gene family member EDNRA is also a top candidate gene in Tibetans (Simonson et al. 2010). BHLHE41, although not associated with hemoglobin, is a key HIF pathway gene and top selection candidate in Amhara, Oromo, and Tigray Ethiopians (Huerta-Sánchez et al. 2013). In addition to these hypoxia-associated genes, three others (VAV3, which encodes vav guanine nucleotide exchange factor 3, and RORA that encodes the RAR-related orphan receptor A) are reported as top candidates in Amhara Ethiopians (Scheinfeldt et al. 2012). Whole-genome sequence analyses indicate three genes contained within the same region of chromosome 19 identified as adaptive targets in Oromo and Simen Ethiopians, CIC, LIPE, and PAFAH1B3 (that encode capicua transcriptional repressor, lipase E hormone-sensitive type, and platelet- activating factor acetylhydrolase 1b catalytic subunit 2, respectively) have orthologs in Drosophila that afford tolerance to hypoxia (Udpa et al. 2014).
Diet and nutrients in the modulation of infant sleep: A review of the literature
Published in Nutritional Neuroscience, 2018
Nora Schneider, Gisella Mutungi, Javier Cubero
A variety of factors have been reported to influence sleep quality and quantity in infants including genetics, overall health and well-being, environment and nutrition. Genetic studies have identified genes that may be important in the regulation of circadian rhythms, which, in turn, determine the time of sleep onset and waking,17,18 such as serotonin transporter gene polymorphism,19 brain-derived neurotrophic factor encoding genes,20 and BHLHE41 (class E basic helix-loop-helix protein 41), also known as DEC2.21,22
Lithium response in bipolar disorders and core clock genes expression
Published in The World Journal of Biological Psychiatry, 2018
Pierre A. Geoffroy, Emmanuel Curis, Cindie Courtin, Jeverson Moreira, Thomas Morvillers, Bruno Etain, Jean-Louis Laplanche, Frank Bellivier, Cynthia Marie-Claire
At d2, analysis of the coexpression data suggests that NR1D1 expression changes are different from other genes (Table S3). Indeed, significant change differences were observed at d2 between NR1D1 and RORA (P = 0.0095), PER1 (P = 0.037), PER2 (P = 0.0073), ARNTL (P = 0.024), CRY2 (P = 0.0082), BHLHE40 (P = 0.012), CSNK1D (P = 0.0005), TIMELESS (P = 0.0020) and CSNK1E (P = 0.044) and to a lesser extent with BHLHE41 (P = 0.069) and CLOCK (P = 0.054). At d4, analysis of the coexpression data shows significant change differences between BHLHE41 and CRY1 (P = 0.0151) and to a lesser extent PER2 (P = 0.071), ARNTL2 (P = 0.079), and CSNK1E (P = 0.090), but also between CRY1 and RORA (P = 0.074). At d8, analysis of the coexpression data found no change differences between genes (Table S3). Figure 2 shows that circadian gene ‘networks’, as defined by maximal ‘cliques’ in the concordance graph (see Methods), were modified when the cells were incubated with Li compared to the no-Li condition, mainly at d2 and d4, with no influence on the circadian gene ‘network’ at d8. At d2, multivariate analysis results indicate that, in response to Li, BHLHE41 expression pattern is different from all other genes. Other genes tend to be split between two groups (‘clique’): a set including NR1D1, DBP, PER3 and CRY1 that are all modulated homogeneously by Li exposure, and another set including all other genes. NR1D1 seems to have the more distinct regulation compared to genes of the other set. At d4, the situation is less contrasted, with three sets comprising BHLHE41 and RORA (a homogeneously modulated group including CRY1, NR1D1, DBP, PER3, PER1 and BHLHE40), with all the other genes comprising the third set. At d8, there is no clear pattern in the set of maximal cliques, and this method does not allow any more gene group classification, being almost homogeneously expressed.
Circadian rhythms of risk factors and management in atherosclerotic and hypertensive vascular disease: Modern chronobiological perspectives of an ancient disease
Published in Chronobiology International, 2023
Yong-Jian Geng, Michael H. Smolensky, Oliver Sum-Ping, Ramon Hermida, Richard J. Castriotta
REV-ERBs and RORs compete to occupy RORs/REV-ERBs-responsive elements (RREs) located in the promoter/enhancer regions of their target genes. RORs usually activate RRE-mediated transcription, whereas REV-ERBs strongly suppress it (Preitner et al. 2002; Sato et al. 2004; Ueda et al. 2002). This stabilizing loop was originally considered as accessory because only moderate phenotypes were observed in mutant mice bearing null alleles of any of these genes. However, subsequent studies utilizing inducible double knockouts for both NR1D1 and NR1D2 revealed that their compensatory activity yielded these subtle phenotypes and that REV-ERBs are required for normal circadian period regulation (Cho et al. 2012). REV-ERBs also control circadian outputs by cooperating with cell-type specific transcriptional regulators (Chung et al. 2014; Zhang et al. 2015). Additional feedback loops involving proline and acidic amino acid-rich basic leucine zipper proteins (PARbZip), such as D-box binding protein (DBP) and E4 promoter-binding protein 4 (E4BP4), plus several members of the bHLH transcription family (BHLHE40 and BHLHE41) also intersect with the main loops to further regulate and mediate circadian expression of subsets of clock-controlled genes (Honma et al. 2002; Mitsui et al. 2001). The circadian nuclear receptors REV-ERBs and RORs mediate many physiological processes, such as regulation of circadian rhythms, development, metabolism, immunity and brain functioning. Members of the nuclear receptor superfamily are ligand-activated transcription factors that act as intracellular receptors for cell-permeable ligands. Recent studies have discovered native, endogenous ligands (e.g., cholesterol oxides or oxysterols) for these circadian nuclear receptors, thereby encouraging the development of synthetic ligands for therapeutic application to manage circadian rhythm-related diseases (Kojetin and Burris 2014). Changes in clock gene expression may contribute to the pathogenesis of atherosclerosis. Aberrant circadian rhythms, increased pathological remodeling, vascular endothelial dysfunction, as well as attenuation of Akt and nitric oxide signaling have been found in the arteries of mice with Bmal1-deficiency and Clock mutation (Anea et al. 2009). Bmal1 deficiency induces oxidative stress, inflammation and atherosclerosis in ApoE-null mice (Xie et al. 2020). Furthermore, human carotid plaque-derived smooth muscle cells display circadian patterns of Bmal1, Cry1, Cry2, Per1, Per2, Per3 and Rev-erb-α mRNA that differ from those of normal carotid arterial tissue (Lin et al. 2014).