Search results for "Life"
showing 10 items of 24622 documents
GreenCut proteinCPLD49 ofChlamydomonas reinhardtiiassociates with thylakoid membranes and is required for cytochromeb6fcomplex accumulation
2018
The GreenCut encompasses a suite of nucleus-encoded proteins with orthologs among green lineage organisms (plants, green algae), but that are absent or poorly conserved in non-photosynthetic/heterotrophic organisms. In Chlamydomonas reinhardtii, CPLD49 (Conserved in Plant Lineage and Diatoms49) is an uncharacterized GreenCut protein that is critical for maintaining normal photosynthetic function. We demonstrate that a cpld49 mutant has impaired photoautotrophic growth under high-light conditions. The mutant exhibits a nearly 90% reduction in the level of the cytochrome b6 f complex (Cytb6 f), which impacts linear and cyclic electron transport, but does not compromise the ability of the stra…
Parallel diversifications of Cremastosperma and mosannona (annonaceae), tropical rainforest trees tracking neogene upheaval of South America
2018
Much of the immense present day biological diversity of Neotropical rainforests originated from the Miocene onwards, a period of geological and ecological upheaval in South America. We assess the impact of the Andean orogeny, drainage of Lake Pebas and closure of the Panama isthmus on two clades of tropical trees ( Cremastosperma , ca 31 spp.; and Mosannona , ca 14 spp.; both Annonaceae). Phylogenetic inference revealed similar patterns of geographically restricted clades and molecular dating showed diversifications in the different areas occurred in parallel, with timing consistent with Andean vicariance and Central American geodispersal. Ecological niche modelling approaches show phyloge…
De novo transcriptome assembly and developmental mode specific gene expression of Pygospio elegans
2017
Species with multiple different larval developmental modes are interesting models for the study of mechanisms underlying developmental mode transitions and life history evolution. Pygospio elegans, a small, tube-dwelling polychaete worm commonly found in estuarine and marine habitats around the northern hemisphere, is one species with variable developmental modes. To provide new genomic resources for studying P. elegans and to address the differences in gene expression between individuals producing offspring with different larval developmental modes, we performed whole transcriptome Illumina RNA sequencing of adult worms from two populations and prepared a de novo assembly of the P. elegans…
New national and regional bryophyte records, 48
2016
Andreaea rothii has been recorded for the first time in Croatia. It is a boreo-temperate suboceanic species (Hill et al., 2007) relatively rare in SE Europe, since it is known only from Romania (Ellis et al., 2014d), Slovenia and Serbia (Sabovljevic´ et al., 2008 ; Hodgetts, 2015). The species was found in the Papuk Mountains, situated in the mainly lowland area of NE Croatia. In this region Papuk is the largest and highest mountain range, with peaks between 800 and 900 m a.s.l. They are characterized by high geological diversity dominated by metamorphic rocks, such as different types of schists, as well as granites. The climate is temperate, moderately warm without an explicit dry period. …
Ecological plant epigenetics: Evidence from model and non-model species, and the way forward
2017
Growing evidence shows that epigenetic mechanisms contribute to complex traits, with implications across many fields of biology. In plant ecology, recent studies have attempted to merge ecological experiments with epigenetic analyses to elucidate the contribution of epigenetics to plant phenotypes, stress responses, adaptation to habitat, and range distributions. While there has been some progress in revealing the role of epigenetics in ecological processes, studies with non-model species have so far been limited to describing broad patterns based on anonymous markers of DNA methylation. In contrast, studies with model species have benefited from powerful genomic resources, which contribute…
Morphological and genetic analyses reveal a cryptic species complex in the echinoid Echinocardium cordatum and rule out a stabilizing selection expla…
2014
14 pages; International audience; Preliminary analyses revealed the presence of at least five mitochondrial clades within the widespread sea urchin Echinocardium cordatum (Spatangoida). In this study, we analyzed the genetic (two mitochondrial and two nuclear sequence loci) and morphological characteristics (20 indices) from worldwide samples of this taxon to establish the species limits, morphological diversity and differentiation. Co-occurring spatangoid species were also analyzed with mitochondrial DNA. The nuclear sequences confirm that mitochondrial lineages correspond to true genetic entities and reveal that two clades (named A and B1) hybridize in their sympatry area, although a more…
Are immune responses gender-related in Carabus lefebvrei (Coleoptera: Carabidae)?
2016
The “live hard, die young” theory predicts the evolution of gender differences in immunocompetence, with males having a weaker immune system than females. To test this hypothesis in Carabus lefebvrei, total and basal phenoloxidase (PO) activities and lysozyme-like enzyme activity were compared among males and females of different reproductive status. The sexual dimorphism occurred only in reproductively active adults and for total and basal PO levels, while no significant differences were recorded between sexes in virgin adults. Differences were not recorded for lytic activity between sexes. Basal PO and lytic activities decreased in both males and females after mating, while the total PO v…
Understanding processes at the origin of species flocks with a focus on the marine Antarctic fauna
2017
Species flocks (SFs) fascinate evolutionary biologists who wonder whether such striking diversification can be driven by normal evolutionary processes. Multiple definitions of SFs have hindered the study of their origins. Previous studies identified a monophyletic taxon as a SF if it displays high speciosity in an area in which it is endemic (criterion 1), high ecological diversity among species (criterion 2), and if it dominates the habitat in terms of biomass (criterion 3); we used these criteria in our analyses. Our starting hypothesis is that normal evolutionary processes may provide a sufficient explanation for most SFs. We thus clearly separate each criterion and identify which biolog…
Surrounding pathogens shape maternal egg care but not egg production in the European earwig
2017
Earwig mothers increase egg care when pathogens are present in the nest, but do not adapt the quantity and quality of their eggs accordingly. Our results confirm that parents can both detect the presence of microbial pathogens in their nesting area and develop pre-hatching behavioral strategies to reduce the associated risk of pathogen infection. These findings overall emphasize the central importance of pathogens in the evolution of parental care in animals.Twitter: @JMeunierEarwig
Transcriptomic responses to environmental change in fishes: Insights from RNA sequencing
2017
The need to better understand how plasticity and evolution affect organismal responses to environmental variability is paramount in the face of global climate change. The potential for using RNA sequencing (RNA-seq) to study complex responses by non-model organisms to the environment is evident in a rapidly growing body of literature. This is particularly true of fishes for which research has been motivated by their ecological importance, socioeconomic value, and increased use as model species for medical and genetic research. Here, we review studies that have used RNA-seq to study transcriptomic responses to continuous abiotic variables to which fishes have likely evolved a response and th…