569 research outputs found
Ready for Our Trip to Mars? Turning the Red Planet Blue
Mars exploration is one of the major current scientific breakthroughs. NASA is actively developing its Mars Exploration Program through several rovers and orbiters to better understand the origin and current conditions of the Red Planet. Since Mars is more Earth-like than any other planet, understanding its formation and evolution could enable to better understand our own origin. Mars is also considered as a future destination for survival of humankind, assuming our ability to face remaining technical challenges, such as radiation risks, extreme conditions, food and medicine supplies. The recent evidence of liquid water on Mars suggests that life could exist, and will be seeked by NASA Mars 2020 rover. Thus, Mars exploration opens remarkable perspectives towards the discovery of new resources and the humanity's expansion. But this tremendous potential also implies completely new questions: what will happen to the Earth if humans are able to escape from global warming and pollution? How will the Martian land be shared between Nations? Will it be impacted by political conflicts on the Earth? If life exists on Mars, will it be compatible with humans? As we get closer to Mars colonization every day, these questions should be addressed and considered as a new chance to envision a world that could benefit from the lessons of History. So, in addition to technical and scientific progress, Mars exploration gives us the chance to redefine our society as a whole
A novel point mutation within the EDA gene causes an exon dropping in mature RNA in Holstein Friesian cattle breed affected by X-linked anhidrotic ectodermal dysplasia
<p>Abstract</p> <p>Background</p> <p>X-linked anhidrotic ectodermal dysplasia is a disorder characterized by abnormal development of tissues and organs of ectodermal origin caused by mutations in the <it>EDA </it>gene. The bovine <it>EDA </it>gene encodes the ectodysplasin A, a membrane protein expressed in keratinocytes, hair follicles and sweat glands, which is involved in the interactions between cell and cell and/or cell and matrix. Four mutations causing ectodermal dysplasia in cattle have been described so far.</p> <p>Results</p> <p>We identified a new single nucleotide polymorphism (SNP) at the 9<sup>th </sup>base of exon 8 in the <it>EDA </it>gene in two calves of Holstein Friesian cattle breed affected by ectodermal dysplasia. This SNP is located in the exonic splicing enhancer (ESEs) recognized by SRp40 protein. As a consequence, the spliceosome machinery is no longer able to recognize the sequence as exonic and causes exon skipping. The mutation determines the deletion of the entire exon (131 bp) in the RNA processing, causing a severe alteration of the protein structure and thus the disease.</p> <p>Conclusion</p> <p>We identified a mutation, never described before, that changes the regulation of alternative splicing in the <it>EDA </it>gene and causes ectodermal dysplasia in cattle. The analysis of the SNP allows the identification of carriers that can transmit the disease to the offspring. This mutation can thus be exploited for a rational and efficient selection of unequivocally healthy cows for breeding.</p
Microarray gene expression profiling of neural tissues in bovine spastic paresis
Abstract: Background: Bovine Spastic Paresis (BSP) is a neuromuscular disorder which affects both male and female cattle. BSP is characterized by spastic contraction and overextension of the gastrocnemious muscle of one or both limbs and is associated with a scarce increase in body weight. This disease seems to be caused by an autosomal and recessive gene, with incomplete penetration, although no genes clearly involved with its onset have been so far identified. We employed cDNA microarrays to identify metabolic pathways affected by BSP in Romagnola cattle breed. Investigation of those pathways at the genome level can help to understand this disease.
Results: Microarray analysis of control and affected individuals resulted in 268 differentially expressed genes. These genes were subjected to KEGG pathway functional clustering analysis, revealing that they are predominantly involved in Cell Communication, Signalling Molecules and Interaction and Signal Transduction, Diseases and Nervous System classes. Significantly enriched KEGG pathway's classes for the differentially expressed genes were calculated; interestingly, all those significantly under-expressed in the affected samples are included in Neurodegenerative Diseases. To identify genome locations possibly harbouring gene(s) involved in the disease, the chromosome distribution of the differentially expressed genes was also investigated.
Conclusions: The cDNA microarray we used in this study contains a brain library and, even if carrying an incomplete transcriptome representation, it has proven to be a valuable tool allowing us to add useful and new information to a poorly studied disease. By using this tool, we examined nearly 15000 transcripts and analysed gene pathways affected by the disease. Particularly, our data suggest also a defective glycinergic synaptic transmission in the development of the disease and an alteration of calcium signalling proteins. We provide data to acquire knowledge of a genetic disease for which literature still presents poor results and that could be further and specifically analysed in the next future. Moreover this study, performed in livestock, may also harbour molecular information useful for understanding human diseases
Predicting Cell Death and Mutation Frequency for a Wide Spectrum of LET by Assuming DNA Break Clustering Inside Repair Domains
Cosmic radiation, which is composed of high charged and energy (HZE) particles, is responsible for cell death and mutation, which may be involved in cancer induction. Mutations are consequences of mis-repaired DNA breaks especially double-strand breaks (DSBs) that induce inter- and intra-chromosomal rearrangements (translocations, deletions, inversion). In this study, a computer simulation model is used to investigate the clustering of DSBs in repair domains, previously evidenced by our group in human breast cells [1]. This model is calibrated with experimental data measuring persistent 53BP1 radiation-induced foci (RIF) and is used to explain the high relative biological effectiveness (RBE) of HZE for both cell death and DNA mutation frequencies. We first validate our DSB cluster model using a new track structure model deployed on a simple geometrical configuration for repair domains in the nucleus; then we extend the scope from cell death to mutation induction. This work suggests that mechanism based on DSB repair process can explain several biological effects induced by HZE particles on different type of living cell
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