19 research outputs found
Deregulation of HMGA1 expression induces chromosome instability through regulation of spindle assembly checkpoint genes
The mitotic spindle assembly checkpoint (SAC) is an essential control system of the cell cycle that contributes to mantain the genomic stability of eukaryotic cells. SAC genes expression is often deregulated in cancer cells, leading to checkpoint impairment and chromosome instability. The mechanisms responsible for the transcriptional regulation and deregulation of these genes are still largely unknown. Herein we identify the nonhistone architectural nuclear proteins High Mobility Group A1 (HMGA1), whose overexpression is a feature of several human malignancies and has a key role in cancer progression, as transcriptional regulators of SAC genes expression. In particular, we show that HMGA1 proteins are able to increase the expression of the SAC genes Ttk, Mad2l1, Bub1 and Bub1b, binding to their promoter regions. Consistently, HMGA1-depletion induces SAC genes downregulation associated to several mitotic defects. In particular, we observed a high number of unaligned chromosomes in metaphase, a reduction of prometaphase time, a delay of anaphase, a higher cytokinesis time and a higher percentage of cytokinesis failure by using live-cell microscopy. Finally, a significant direct correlation between HMGA1 and SAC genes expression was detected in human colon carcinomas indicating a novel mechanism by which HMGA1 contributes to cancer progression
Disruption of paternal circadian rhythm affects metabolic health in male offspring via nongerm cell factors
Circadian rhythm synchronizes each body function with the environment and regulates physiology. Disruption of normal circadian rhythm alters organismal physiology and increases disease risk. Recent epidemiological data and studies in model organisms have shown that maternal circadian disruption is important for offspring health and adult phenotypes. Less is known about the role of paternal circadian rhythm for offspring health. Here, we disrupted circadian rhythm in male mice by night-restricted feeding and showed that paternal circadian disruption at conception is important for offspring feeding behavior, metabolic health, and oscillatory transcription. Mechanistically, our data suggest that the effect of paternal circadian disruption is not transferred to the offspring via the germ cells but initiated by corticosterone-based parental communication at conception and programmed during in utero development through a state of fetal growth restriction. These findings indicate paternal circadian health at conception as a newly identified determinant of offspring phenotypes
Identifying causal serum protein-cardiometabolic trait relationships using whole genome sequencing
Insights into energy balance dysregulation from a mouse model of methylmalonic aciduria
Inherited disorders of mitochondrial metabolism, including isolated methylmalonic aciduria, present unique challenges to energetic homeostasis by disrupting energy-producing pathways. To better understand global responses to energy shortage, we investigated a hemizygous mouse model of methylmalonyl-CoA mutase (Mmut)âtype methylmalonic aciduria. We found Mmut mutant mice to have reduced appetite, energy expenditure and body mass compared with littermate controls, along with a relative reduction in lean mass but increase in fat mass. Brown adipose tissue showed a process of whitening, in line with lower body surface temperature and lesser ability to cope with cold challenge. Mutant mice had dysregulated plasma glucose, delayed glucose clearance and a lesser ability to regulate energy sources when switching from the fed to fasted state, while liver investigations indicated metabolite accumulation and altered expression of peroxisome proliferatorâactivated receptor and Fgf21-controlled pathways. Together, these shed light on the mechanisms and adaptations behind energy imbalance in methylmalonic aciduria and provide insight into metabolic responses to chronic energy shortage, which may have important implications for disease understanding and patient management
Insights into energy balance dysregulation from a mouse model of methylmalonic aciduria
Inherited disorders of mitochondrial metabolism, including isolated methylmalonic aciduria (MMAuria), present unique challenges to energetic homeostasis by disrupting energy producing pathways. To better understand global responses to energy shortage, we investigated a hemizygous mouse model of methylmalonyl-CoA mutase (Mmut) type MMAuria. We found Mmut mutant mice to have reduced appetite, energy expenditure and body mass compared to littermate controls, along with a relative reduction in lean mass but increase in fat mass. Brown adipose tissue showed a process of whitening, in line with lower body surface temperature and lesser ability to cope with cold challenge. Mutant mice had dysregulated plasma glucose, delayed glucose clearance and a lesser ability to regulate energy sources when switching from the fed to fasted state, while liver investigations indicated metabolite accumulation and altered expression of peroxisome proliferator-activated receptor and Fgf21-controlled pathways. Together, these indicate hypometabolism, energetic inflexibility and increased stores at the expense of active tissue as energy shortage consequences
Energy recovery from landfill gas at Giugliano plant: first results
The project is based on a new cogeneration plant to be located by the Giugliano landfill, near Naples. The landfill gas will be exploited in a hybrid cogeneration system made up by four reciprocating engines, a gas turbine, two Molten Carbonate Fuel Cells (MCFC) and a Solid Oxide Fuel Cells (SOFC). The overall installed capacity will be about 6.2 MW. In this paper, detailed information is provided about plant design, with special attention to some non-conventional aspects, such as the ones regarding the thermal treatment of leachate and the use of biogas in fuel cells. Furthermore, the results expected from plant operation are analyzed, providing information about mass and energy balance, plant efficiency and environmental impact. Finally the first results regarding the operation of the reciprocating engines are presented
ITag-RNA Allows in Vivo Cell-Type Specific Transcriptional Characterization and Tracking of Circulating Transcripts
Hmga1 null mouse embryonic fibroblasts display downregulation of spindle assembly checkpoint gene expression associated to nuclear and karyotypic abnormalities
The High Mobility Group A1 proteins (HMGA1) are nonhistone chromatinic proteins with a critical role in development and cancer. We have recently reported that HMGA1 proteins are able to increase the expression of spindle assembly checkpoint (SAC) genes, thus impairing SAC function and causing chromosomal instability in cancer cells. Moreover, we found a significant correlation between HMGA1 and SAC genes expression in human colon carcinomas. Here, we report that mouse embryonic fibroblasts null for the Hmga1 gene show downregulation of Bub1, Bub1b, Mad2l1 and Ttk SAC genes, and present several features of chromosomal instability, such as nuclear abnormalities, binucleation, micronuclei and karyotypic alterations. Interestingky, also MEFs carrying only one impaired Hmga1 allele present karyotypic alterations. These results indicate that HMGA1 proteins regulate SAC genes expression and, thereby, genomic stability also in embryonic cells
Glix 13, a new drug acting on glutamatergic pathways in children and animal models of autism spectrum disorders
Recently standardized diagnostic instruments have been developed in diagnostic and therapeutic procedures for Autism Spectrumv Disorders (ASD). According to the DSM-5 criteria, individuals with ASD must show symptoms from early childhood. These symptoms are communication deficits and restricted, repetitive patterns of behaviour. It was recently described by Bioinformatic analysis that 99 modified genes were associated with human autism. Gene expression patterns in the low-line animals show significant enrichment in autism-associated genes and the NMDA receptor gene family was identified among these. Using ultrasonic vocalizations, it was demonstrated that genetic variation has a direct impact on the expression of social interactions. It has been proposed that specific alleles interact with a social reward process in the adolescent mouse modifying their social interaction and their approach toward each other. In this review we report that the monoclonal antibody-derived tetrapeptide GLYX-13 was found to act as an N-methyl-D-aspartate receptor modulator and possesses the ability to readily cross the blood brain barrier. Treatment with the NMDAR glycine site partial agonist GLYX-13 rescued the deficit in the animal model. Thus, the NMDA receptor has been shown to play a functional role in autism, and GLYX-13 shows promise for the treatment of autism in autistic children