Circadian clocks regulate behavioral, physiological and biochemical processes in a day/night cycle. Circadian oscillators have an essential role in the coordination of physiological processes with the cyclic changes in the physical environment. Such mammalian circadian clocks composed of the positive components (BMAL1 and CLOCK) and the negative components (CRY and PERIOD (PER)) are regulated by a negative transcriptional feedback loop in which PER is rate-limiting for feedback inhibition. In addition, posttranslational modification of these components is critical for setting or resetting the circadian oscillation. Circadian regulation of metabolism is mediated through reciprocal signaling between the clock and metabolic regulatory networks. AMP-activated protein kinase (AMPK) in the brain and peripheral tissue is a crucial cellular energy sensor that has a role in metabolic control. AMPK-mediated phosphorylation of CRY and Casein kinases I regulates the negative feedback control of circadian clock by proteolytic degradation. AMPK can also modulate the circadian rhythms through nicotinamide adenine dinucleotide-dependent regulation of silent information regulator 1. Growing evidence elucidates the AMPK-mediated controls of circadian clock in metabolic diseases such as obesity and diabetes. In this review, we summarize the current comprehension of AMPK-mediated regulation of the circadian rhythms. This will provide insight into understanding how their components regulate the metabolism.
AMP-Activated Protein Kinases/*metabolism ; Animals ; Casein Kinase I/metabolism ; *Circadian Clocks ; Cryptochromes/metabolism ; Humans ; *Metabolism ; Sirtuins/metabolism

OBJECTIVETo investigate the association between single nucleotide polymorphisms (SNPs) of casein kinase I gamma 2 (CSNK1G2) gene and children with familial febrile convulsions.

METHODSThe study samples were collected from unrelated Chinese Han population of Hebei province, including a cohort of 53 children with familial febrile convulsions(FC) and a control cohort of 101 individuals. Genotypes of SNPs rs2074882, rs740423, rs2277737, rs4806825, rs1059684 were typed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTSThe frequencies of the five SNPs complied well with the Hardy-Weinberg equilibrium in FC group and normal group. The distribution of genotype and frequencies of alleles of the SNPs rs740423, rs2277737, rs1059684 in familial febrile convulsions group was significantly different from that in control group. No significant difference was observed in the distribution of genotypes and frequencies of alleles at SNP rs2074882 between two groups. Analysis on rs4806825 was not made owing to its less allele frequency.

CONCLUSIONThese data indicate that SNPs rs740423, rs2277737, rs1059684 of CSNK1G2 gene may contribute to familial febrile convulsions in children.

Casein Kinase I ; genetics ; Child, Preschool ; Family Health ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; genetics ; Genotype ; Humans ; Infant ; Linkage Disequilibrium ; Male ; Polymerase Chain Reaction ; Polymorphism, Single Nucleotide ; Seizures, Febrile ; genetics