66 research outputs found
Full moonlight-induced circadian clock entrainment in Coffea arabica
Background: It is now well documented that moonlight affects the life cycle of invertebrates, birds, reptiles, and mammals. The lunisolar tide is also well-known to alter plant growth and development. However, although plants are known to be very photosensitive, few studies have been undertaken to explore the effect of moonlight on plant physiology. Results: Here for the first time we report a massive transcriptional modification in Coffea arabica genes under full moonlight conditions, particularly at full moon zenith and 3 h later. Among the 3387 deregulated genes found in our study, the main core clock genes were affected. Conclusions: Moonlight also negatively influenced many genes involved in photosynthesis, chlorophyll biosynthesis and chloroplast machinery at the end of the night, suggesting that the full moon has a negative effect on primary photosynthetic machinery at dawn. Moreover, full moonlight promotes the transcription of major rhythmic redox genes and many heat shock proteins, suggesting that moonlight is perceived as stress. We confirmed this huge impact of weak light (less than 6 lx) on the transcription of circadian clock genes in controlled conditions mimicking full moonlight
A chromosome-scale assembly reveals chromosomal aberrations and exchanges generating genetic diversity in Coffea arabica germplasm
In order to better understand the mechanisms generating genetic diversity in the recent allotetraploid species Coffea arabica, here we present a chromosome-level assembly obtained with long read technology. Two genomic compartments with different structural and functional properties are identified in the two homoeologous genomes. The resequencing data from a large set of accessions reveals low intraspecific diversity in the center of origin of the species. Across a limited number of genomic regions, diversity increases in some cultivated genotypes to levels similar to those observed within one of the progenitor species, Coffea canephora, presumably as a consequence of introgressions deriving from the so-called Timor hybrid. It also reveals that, in addition to few, early-occurring exchanges between homoeologous chromosomes, there are numerous recent chromosomal aberrations including aneuploidies, deletions, duplications and exchanges. These events are still polymorphic in the germplasm and could represent a fundamental source of genetic variation in such a lowly variable species
Unraveling the impact of upfront chemotherapy and proton beam therapy on treatment outcome and follow-up in central nervous system germ cell tumors: a single center experience
Background: Germ cell tumors (GCT) account for a minority of central nervous system (CNS) malignancies, highly prevalent in adolescents and young adults. Despite their aggressive biological behavior, prognosis is excellent in most cases with risk stratified treatment, consisting in a combination of chemotherapy and radiotherapy. Whole ventricular irradiation (WVI) and craniospinal irradiation, the treatment of choice for localized and metastatic disease, pose significant risk of collateral effects, therefore proton beam radiation (PBT) has been recently proposed for its steep dose fallout. Materials and methods: We report our experience in a consecutive series of 17 patients treated for CNS GCT at our Institution from 2015 to 2021. Results: Most frequent lesion location were sellar/suprasellar (35%) and bifocal germinoma (35%), followed by pineal (18%) and thalamic (12%). Two patients (12%), had evidence of disseminated disease at the time of diagnosis. At the latest follow-up all but one patient showed complete response to treatment. The only relapse was successfully rescued by additional chemotherapy and PBT. PBT was well tolerated in all cases. No visual, neurological or endocrinological worsening was documented during and after treatment. Neuropsychological evaluation demonstrated preservation of cognitive performance after PBT treatment. Conclusions: Our data, albeit preliminary, strongly support the favourable therapeutic profile of PBT for the treatment of CNS germ cell tumors
Pheno-genotypic and symbiotic characterization of isolated rhizobia of Desmanthus Virgatus (l.) Willd. In soils of the province of Jujuy (Argentina)
Las leguminosas forrajeras nativas presentan un gran potencial productivo y un ejemplo de ellas es Desmanthus virgatus de amplia distribución en el centro norte de Argentina. El objetivo del trabajo fue realizar una caracterización feno-genotípica y simbiótica de rizobios que forman nódulos en D. virgatus con vista hacia el uso sustentable integral de dicha leguminosa. Para ello, se estableció una colección de 17 aislamientos recuperados de suelos de Jujuy. La caracterización fenotípica permitió reconocer rizobios de crecimiento rápido que mostraron un desarrollo óptimo entre pH 5 y 8, temperaturas de 28 a 35°C, y en concentraciones de 1% (p/v) de NaCl. Se hallaron rizobios con capacidad de crecimiento en condiciones extremas de pH 9 y a 40°C. Los aislamientos se identificaron como pertenecientes a Ensifer spp. y los perfiles de amplificación de ADN genómico mostraron escasa diversidad genética. La inoculación de D. virgatus con la cepa 8L12.1 (Ensifer sp.) produjo incrementos de biomasa seca aérea de 73% en cámara de cultivo y 124% a campo respecto a las plantas sin inocular y sin fertilizar.Native forage legumes have great productive potential and an example of which is Desmanthus virgatus with a wide distribution in central and northern Argentina. The objective of the work was to carry out a pheno-genotypic and symbiotic characterization of rhizobia that form nodules in D. virgatus with a view to the integral sustainable use of said legume. For this, a collection of 17 isolates recovered from Jujuy soils was established. Phenotypic characterization allowed to recognize fast-growing rhizobia that showed an optimal development between pH 5 y 8, temperatures to 28 a 35°C, and in concentrations of 1% (w/v) of NaCl. Rhizobia with growth capacity were found under extreme conditions of pH 9 and at 40°C. The isolates were identified as belonging to Ensifer spp.
and the genomic DNA amplification profiles showed little genetic diversity. The inoculation of D. virgatus with the strain 8L12.1 (Ensifer sp.) produced increases of 73% aerial dry biomass in the cultivation chamber and 124% in the field with respect to the uninoculated and unfertilized plants.Instituto de Biotecnologia y Biologia Molecula
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