Search results for "Complex"
showing 10 items of 5889 documents
Gut microbiota of the pine weevil degrades conifer diterpenes and increases insect fitness
2017
AbstractThe pine weevil (Hylobius abietis), a major pest of conifer forests throughout Europe, feeds on the bark and cambium, tissues rich in terpenoid resins that are toxic to many insect herbivores. Here we report the ability of the pine weevil gut microbiota to degrade the diterpene acids of Norway spruce. The diterpene acid levels present in ingested bark were substantially reduced on passage through the pine weevil gut. This reduction was significantly less upon antibiotic treatment, and supplementing the diet with gut suspensions from untreated insects restored the ability to degrade diterpenes. In addition, cultured bacteria isolated from pine weevil guts were shown to degrade a Norw…
Plant Responses to Abiotic Stress Regulated by Histone Deacetylases
2017
In eukaryotic cells, histone acetylation and deacetylation play an important role in the regulation of gene expression. Histone acetylation levels are modulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs). Recent studies indicate that HDACs play essential roles in the regulation of gene expression in plant response to environmental stress. In this review, we discussed the recent advance regarding the plant HDACs and their functions in the regulation of abiotic stress responses. The role of HDACs in autophagy was also discussed.
Alternative Splicing of the Basic Helix–Loop–Helix Transcription Factor Gene CmbHLH2 Affects Anthocyanin Biosynthesis in Ray Florets of Chrysanthemum…
2021
Chrysanthemum is an important ornamental crop worldwide. Some white-flowered chrysanthemum cultivars produce red ray florets under natural cultivation conditions, but little is known about how this occurs. We compared the expression of anthocyanin biosynthetic and transcription factor genes between white ray florets and those that turned red based on cultivation conditions to comprehend the underlying mechanism. Significant differences in the expression of CmbHLH2 were detected between the florets of different colors. CmbHLH2 generated two alternatively spliced transcripts, designated CmbHLH2Full and CmbHLH2Short. Compared with CmbHLH2Full, CmbHLH2Short encoded a truncated protein with only…
Selection for multicomponent mimicry: equal feature salience and variation in preferred traits
2016
When should multiple traits on Batesian mimics be selected to resemble corresponding traits on model species? Here, we explore two possibilities. First, features of equal salience to predators may be used to categorize prey, selecting for multicomponent mimicry. Second, if different predators use single yet different traits to categorize prey, multicomponent mimicry may still be selected. We studied how blue tits categorized rewarding and unrewarding artificial prey items that are differentiated by a combination of two color dimensions. Many birds used both color dimensions to make decisions, and overall, the population selected for multicomponent mimicry. However, a subset of birds used on…
Evaluating responses to temperature during pre-metamorphosis and carry-over effects at post-metamorphosis in the wood tiger moth (Arctia plantaginis)
2019
Insect metamorphosis is one of the most recognized processes delimiting transitions between phenotypes. It has been traditionally postulated as an adaptive process decoupling traits between life stages, allowing evolutionary independence of pre- and post-metamorphic phenotypes. However, the degree of autonomy between these life stages varies depending on the species and has not been studied in detail over multiple traits simultaneously. Here, we reared full-sib larvae of the warningly coloured wood tiger moth ( Arctia plantaginis ) in different temperatures and examined their responses for phenotypic (melanization change, number of moults), gene expression (RNA-seq and qPCR of candidate ge…
Evolutionary history of two cryptic species of northern African jerboas
2020
Abstract Background: Climatic variation and geologic change both play significant roles in shaping species distributions, thus affecting their evolutionary history. In Sahara-Sahel, climatic oscillations shifted the desert extent during the Pliocene-Pleistocene interval, triggering the diversification of several species. Here, we investigated how these biogeographical and ecological events have shaped patterns of genetic diversity and divergence in African Jerboas, desert specialist rodents. We focused on two sister and cryptic species, Jaculus jaculus and J. hirtipes, where we (1) evaluated their genetic differentiation, (2) reconstructed their evolutionary and demographic history; (3) tes…
Arabidopsis RCD1 coordinates chloroplast and mitochondrial functions through interaction with ANAC transcription factors
2019
Reactive oxygen species (ROS)-dependent signaling pathways from chloroplasts and mitochondria merge at the nuclear protein RADICAL-INDUCED CELL DEATH1 (RCD1). RCD1 interacts in vivo and suppresses the activity of the transcription factors ANAC013 and ANAC017, which mediate a ROS-related retrograde signal originating from mitochondrial complex III. Inactivation of RCD1 leads to increased expression of mitochondrial dysfunction stimulon (MDS) genes regulated by ANAC013 and ANAC017. Accumulating MDS gene products, including alternative oxidases (AOXs), affect redox status of the chloroplasts, leading to changes in chloroplast ROS processing and increased protection of photosynthetic apparatus.…
Cryptic species unveiled: the case of the nematode Spauligodon atlanticus
2013
The implementation of molecular tools in parasitology has led to the discovery of numerous cryptic species. However, detailed morphological studies are needed to evaluate the cryptic nature of such species, as well as to provide an appropriate and formal description. Recent phylogenetic analyses using mitochondrial and nuclear genes have revealed that the nematode Spauligodon atlanticus, parasite of lizards of the genus Gallotia endemic to the Canary Islands, consists of two highly divergent and unrelated lineages, one in the eastern islands and the other in the western ones. This study provides a detailed morphological analysis of the two S. atlanticus lineages characterized genetically, b…
Remarkable ancient divergences amongst neglected lorisiform primates
2015
Lorisiform primates (Primates: Strepsirrhini: Lorisiformes) represent almost 10% of the living primate species and are widely distributed in sub-Saharan Africa and South/South-East Asia; however, their taxonomy, evolutionary history, and biogeography are still poorly understood. In this study we report the largest molecular phylogeny in terms of the number of represented taxa. We sequenced the complete mitochondrial cytochrome b gene for 86 lorisiform specimens, including ∼80% of all the species currently recognized. Our results support the monophyly of the Galagidae, but a common ancestry of the Lorisinae and Perodicticinae (family Lorisidae) was not recovered. These three lineages have ea…
Phylogeography of two cryptic species of African desert jerboas (Dipodidae: Jaculus)
2012
The lesser Egyptian jerboa Jaculus jaculus is a desert dwelling rodent that inhabits a broad Arabian–Saharan arid zone. Recently, two distant sympatric lineages were described in North-West Africa, based on morphometric and molecular data, which may correspond to two cryptic species. In the current study, phylogenetic relationships and phylogeographical structure among those lineages and geographical populations from North Africa and the Middle East were investigated. The phylogeographical patterns and genetic diversity of the cytochrome b gene (1110 bp) were addressed on 111 jerboas from 41 localities. We found that the variation in Africa is partitioned into two divergent mitochondrial cl…