RESUMEN
Autophagy is a highly conserved self-digestion process, which is essential for maintaining homeostasis and viability in response to nutrient starvation. Although the components of autophagy in the cytoplasm have been well studied, the molecular basis for the transcriptional and epigenetic regulation of autophagy is poorly understood. Here we identify co-activator-associated arginine methyltransferase 1 (CARM1) as a crucial component of autophagy in mammals. Notably, CARM1 stability is regulated by the SKP2-containing SCF (SKP1-cullin1-F-box protein) E3 ubiquitin ligase in the nucleus, but not in the cytoplasm, under nutrient-rich conditions. Furthermore, we show that nutrient starvation results in AMP-activated protein kinase (AMPK)-dependent phosphorylation of FOXO3a in the nucleus, which in turn transcriptionally represses SKP2. This repression leads to increased levels of CARM1 protein and subsequent increases in histone H3 Arg17 dimethylation. Genome-wide analyses reveal that CARM1 exerts transcriptional co-activator function on autophagy-related and lysosomal genes through transcription factor EB (TFEB). Our findings demonstrate that CARM1-dependent histone arginine methylation is a crucial nuclear event in autophagy, and identify a new signalling axis of AMPK-SKP2-CARM1 in the regulation of autophagy induction after nutrient starvation.
Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteínas Quinasas Asociadas a Fase-S/metabolismo , Transducción de Señal , Transcripción Genética , Animales , Arginina/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Línea Celular , Núcleo Celular/metabolismo , Privación de Alimentos , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/deficiencia , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Histonas/metabolismo , Humanos , Lisosomas/genética , Metilación , Ratones , Fosforilación , Proteínas Quinasas Asociadas a Fase-S/antagonistas & inhibidores , Proteínas Ligasas SKP Cullina F-box/química , Proteínas Ligasas SKP Cullina F-box/metabolismoRESUMEN
The genus Sinopoda Jäger, 1999 is a group of huntsman spiders (Araneae: Sparassidae: Heteropodinae), and currently seven species have been reported in Korea. In this study, three new species are described from Korea, Sinopodabigibba sp. nov., Sinopodabogil sp. nov., and Sinopodapantherina sp. nov.; Sinopodajirisanensis Kim & Chae, 2013 is revalidated with neotype designation, and had been formerly synonymized with Sinopodaforcipata (Karsch, 1881). Additionally, all previous records of Sinopodastellatops Jäger & Ono, 2002 and S.forcipata from Korea are deemed misidentifications of S.jirisanensis and S.bogil sp. nov., respectively.
RESUMEN
The South Korean species of the genus Diplonevra are revised and eight species are recognized. Three of these species, D. biflagella, sp. nov., D. incisura, sp. nov., and D. nigritarsis, sp. nov., are new to science and four species, D. abbreviata (von Roser, 1840), D. florescens (Turton, 1801), D. hirsuta Michailovskaya, 2000, and D. peregrina (Wiedemann, 1830), are described for the first time in Korea. Distribution of D. bifasciata (Walker, 1860), the only previously recorded species in Korean checklists, is confirmed based on figures of a female specimen in previous publications. Diplonevra lamella Liu Yang, 2016 is considered a junior synonym of D. hirsuta Michailovskaya, 2000. The Chinese and Russian Far East records of D. pachycera (nec Schmitz) are treated as misidentifications of D. incisura, sp. nov. and D. nigritarsis, sp. nov., respectively. Also, the Chinese record of D. taigaensis (nec Michailovskaya) should be identified as D. biflagella, sp. nov. Detailed descriptions and photographs of three new species and four redescribed species and keys to eight males and seven females of Diplonevra species in South Korea are provided.
Asunto(s)
Dípteros , Distribución Animal , Animales , Femenino , MasculinoRESUMEN
Although the high level of species diversity within the Pholcus phungiformes-group (Araneae: Pholcidae) in the Korean Peninsula has been recognized recently, taxonomic studies, including new species discovery, have not been conducted in western regions of South Korea. In this study, five additional species belonging to the Pholcus phungiformes-group discovered from Seoul and surrounding areas are described as new, viz., Pholcus seoulensis Lee Lee, sp. nov. Pholcus suraksanensis Lee Lee, sp. nov., Pholcus incheonensis Lee Lee, sp. nov., Pholcus seokmodoensis Lee Lee, sp. nov. and Pholcus chilgapsanensis Lee Lee, sp. nov. Detailed descriptions and geographic distributions are provided with accompanying photographs.