Argonaute proteins are active throughout the lifetime in a variety of organisms and they bind to small RNAs (sRNAs) to regulate gene expression. The Argonaute proteins of vertebrates can be classified into two clades: the Ago clade and the Piwi clade. Both clades have N, L1, L2, PAZ, MID and PIWI domains. The N domain is involved in the loading of sRNAs. L1 and L2 domains facilitate the linking between domains. The PAZ and MID domains exert functions by anchoring sRNAs. The PIWI domain of some Argonaute proteins has RNase H-like structure and exerts the endonuclease function. Ago proteins regulate gene expression at transcriptional and post-transcriptional levels. Piwi proteins mainly exist in the germ cells, silencing transposons in different ways to keep genome integrality and regulating gene expression. In recent years, great progress has been made in Argonaute proteins in terms of the crystal structures, functions, and expression patterns. By reviewing the relevant studies, we elaborate on the structures, sRNA dependence, gene expression regulation, and biological roles of the Ago and Piwi proteins in vertebrates, aiming to clarify the roles of Argonaute proteins in epigenetic regulation and provide a reference for further research and application of these proteins.
Argonaute Proteins/chemistry* ; Animals ; Vertebrates/metabolism* ; Gene Expression Regulation ; RNA, Small Interfering/metabolism* ; Epigenesis, Genetic ; Humans

Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of the vertebrates, as well as the synthetic analogs of these hormones that are synthesized in the laboratories. Two main classes of corticosteroids, glucocorticoids, and mineralocorticoids, are involved in a wide range of physiologic processes, including stress response, immune response, and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte levels, and behavior. Corticosteroids have been used for almost 60 years in medicine and their roles in patients have always been discussed by researchers and clinicians dedicated in the related field. Currently, they are still used in the treatment of patients with neurological disorders. Usually, corticosteroids are used in the treatment of various inflammatory diseases and conditions. In this review, we present five key indications, i.e., neuromyelitis optica, acute spinal cord injury, chronic inflammatory demyelinating polyneuropathy, myasthenia gravis, polymyositis/dermatomyositis for the systemic use of corticosteroids in neurology based on a mix of quality of evidence, prevalence, and impact on disease management.
Adrenal Cortex ; Adrenal Cortex Hormones ; Carbohydrate Metabolism ; Disease Management ; Glucocorticoids ; Humans ; Inflammation ; Metabolism ; Mineralocorticoids ; Myasthenia Gravis ; Nervous System Diseases ; Neurology ; Neuromyelitis Optica ; Polyneuropathies ; Prevalence ; Spinal Cord Injuries ; Spinal Cord ; Vertebrates

It already has been known that various ions were participated in phototransduction mechanism of the vertebrate photoreceptor during the visual adaptation. The vitreous humor(VH)contains certain amount of Na+, K+ and Ca++ as well. However, the roles of these ions are unknown except functioning of metabolic process. Our preliminary electroretinogram(ERG) experiments suggested that the permeability of these ions has light dependent activity during the light illumination. We have supported this suggestion more tangibly by trying out various experiments with bullfrog eyes as a reference of visual adaptation. The results are summarized as follows: 1)According to our atomic absorption spectroscopic measurements, the concentration of Na+, K+ and Ca++ in light adapted VH was higher than that of dark adapted VH. This result indicated that the light-dependention transport systems which affect the ionic movements might be in internal limiting membrane(ILM). 2)The amplitude of ERG b-wave was reduced by concentration decrement of Na+ and concentration increment of K+ respectively. On the other hand, the elimination of Ca++ within ringer solution resulted in b-wave amplitude increment. 3)Treatment of Na+ hannel blockers(TTX, STX)and K+ channel blockers(Ba++, Cd++, Cs+, 4-AP and TEA)in the vitreous humor side induced the increment and the decrement of b-wave response respectively. Taken together, these results suggest that the light dependent Na+ K+ channels exist in the ILM of vertebrate retina which participates visual adaptation.
Absorption ; Hand ; Ions ; Light Signal Transduction ; Lighting ; Membranes* ; Metabolism ; Permeability ; Photoreceptor Cells, Vertebrate ; Rana catesbeiana ; Retina ; Vertebrates* ; Vitreous Body