Project description:Rhododendron is well known woody plant, as having high ornamental and economic values. Heat stress is one of the important environmental stresses that effects Rhododendron growth. Recently, melatonin was reported to alleviate abiotic stress in plants. However, the role of melatonin in Rhododendron is still unknown. In the present study, the effect of melatonin on Rhododendron under heat stress and the potential mechanism was investigated. Through morphological characterization and chlorophyll a fluorescence analysis, 200µM was selected for the best melatonin concentration to mitigate heat stress in Rhododendron. To reveal the mechanism of melatonin priming alleviating the heat stress, the photosynthesis indexes, Rubisco activity and ATP content were detected in 25 ℃, 35 ℃ and 40 ℃. The results showed that melatonin improves electron transport rate (ETR), PSII and PSI activity, Rubisco activity and ATP content under high temperature stress. Furthermore, transcriptome analysis showed that a significant enrichment of differentially expressed genes in the photosynthesis pathway, and most of genes in photosynthesis pathway displayed a more significantly slight down-regulation under high temperature stress in melatonin-treatment plants, compared with melatonin-free plants. We identified PGR5……Together, these results demonstrate that melatonin could promote the photosynthetic electron transport, improve the enzymes activities in Calvin cycle and the production of ATP, and thereby increase photosynthetic efficiency and CO2 assimilation capacity under heat stress, through regulating the expression of some key genes, such as PGR5…Therefore, melatonin application displayed great potential to cope with the heat stress in Rhododendron.
Project description:Lactobacillus casei is remarkably adaptive to diverse habitats. To understand the evolution and adaptation of Lb. casei strains isolated from different environments, the gene content of 22 Lb. casei strains isolated from various habitats (cheeses, n=8; plant materials, n=8; and human sources, n=6) were examined by comparative genome hybridization with an Lb. casei ATCC 334-based microarray.
Project description:Many insects enter a developmental arrest (diapause) that allows them to survive harsh seasonal conditions. Despite the well-established ecological significance of diapause, the molecular basis of this crucial adaptation remains largely unresolved. Sitodiplosis mosellana (Gehin), the orange wheat blossom midge (OWBM), causes serious damage to wheat throughout the northern hemisphere, and sporadic outbreaks occur in the world. Traits related to diapause appear to be important factors contributing to their rapid spread and outbreak. To better understand the diapause mechanisms of OWBM, we sequenced the transcriptome and determined the gene expression profile of this species.
Project description:Lactobacillus casei is remarkably adaptive to diverse habitats. To understand the evolution and adaptation of Lb. casei strains isolated from different environments, the gene content of 22 Lb. casei strains isolated from various habitats (cheeses, n=8; plant materials, n=8; and human sources, n=6) were examined by comparative genome hybridization with an Lb. casei ATCC 334-based microarray. Comparative genome hybridization was performed against an Affymetrix custom microarray designed to include 2,661 (97%) chromosomal and 17 (85%) plasmid CDSs predicted to occur in Lb. casei ATCC 334, as well as all predicted CDSs in the draft Lb. helveticus CNRZ 32 genome. CDSs that were not included in the microarray design were all transposase-encoding genes.
Project description:Apis laboriosa, the Himalayan giant honey bee, is a species of honey bees (genus Apis), which is highly adapted to highland habitats and mainly occurs in mountainous regions, particularly the Himalayas. Up to data, the genetic basis of its high-elevation adaptation remains a mystery. In the present study, we generated transcriptomes for A. laboriosa and its closely related species A. dorsata, we then characterized the transcriptomes and did comparative and evolutionary analysis between them to understand the genetic basis of high-altitude adaptation in A. laboriosa. We identified 1,605 genes that are absent in A. dorsata but present in A. laboriosa. Those A. laboriosa-specific genes were involved in DNA damage repair, low temperature tolerance and oxidative stress response. In addition, for genes shared by the two species, genes related to anoxia tolerance, freeze tolerance and UV irradiation were positively selected in A. laboriosa. Taken together, our results suggest that both the increased copy number and the accelerated protein sequence evolution of genes related to high-elevation adaptation made a difference between A. laboriosa and A. dorsata, which should contribute to the adaptation of A. laboriosa to challenging environments in Himalayas.
Project description:During the over 300 million years of co-evolution between herbivorous insects and their host plants, a dynamic equilibrium of evolutionary arms race has been established. However, the co-adaptation between insects and their host plants is a complex process, often driven by multiple evolutionary mechanisms. We found that various lepidopteran pests that use maize as a host exhibit differential adaptation to the plant secondary metabolites, benzoxazinoids (BXs). Notably, the Spodoptera genus, including Spodoptera frugiperda (fall armyworm) and Spodoptera litura (cotton leafworm), demonstrate greater tolerance to BXs compared to other insects. Through comparative transcriptomic analysis of the midgut, we identified four candidate genes potentially involved in BXs detoxification in S. frugiperda. Subsequently, we confirmed two UGT genes, Sfru33T10 and Sfru33F32, as key players in BXs detoxification using CRISPR/Cas9 gene-editing technology. Phylogenetic analysis revealed that Sfru33T10 evolved independently within the Noctuidae family and is involved in the glycosylation of HDMBOA, while Sfru33F32 evolved independently within the Spodoptera genus and functions as a key detoxification enzyme responsible for the glycosylation of both DIMBOA and HMBOA. Our study demonstrates that the UGT gene family plays a crucial role in the adaptation of noctuid insects to maize, with multiple independent evolutionary events within the Noctuidae family and the Spodoptera genus contributing significantly to host adaptation.
Project description:The enterococci comprise a genus of 49 low-GC content Gram-positive commensal species within the Firmicutes phylum that are known to occupy diverse habitats, notably the gastrointestinal core microbiota of nearly every phylum, including human. Of particular clinical relevance are two rogue species of enterococci, Enterococcus faecalis and the distantly related Enterococcus faecium, standing among the nefarious multi-drug resistant and hospital-acquired pathogens. Despite increasing evidence for RNA-based regulation in the enterococci, including regulation of virulence factors, their transcriptome structure and arsenal of regulatory small sRNAs (sRNAs) are not thoroughly understood. Using dRNA-seq, we have mapped at single-nucleotide resolution the primary transcriptomes of E. faecalis V583 and E. faecium AUS0004. We identified 2517 and 2771 transcription start sites (TSS) in E. faecalis and E. faecium, respectively. Based on the identified TSS, we created a global map of s70 promoter motifs. We also revealed features of 5’ and 3’UTRs across the genomes. The transcriptome maps also predicted 150 and 128 sRNA candidates in E. faecalis and E. faecium, respectively, some of which have been identified in previous studies and many of which are new. Finally, we validated several of the predicted sRNAs by Northern Blot in biologically relevant conditions. Comprehensive TSS mapping of two representative strains will provide a valuable resource for the continued development of RNA biology in the Enterococci.
Project description:Vibrio species represent one of the most diverse genera of marine bacteria known for their ubiquitous presence in natural aquatic systems. Several members of this genus including Vibrio harveyi are receiving increasing attention lately because they are becoming a source of health problems, especially for some marine organisms widely used in sea food industry. To learn about adaptation changes triggered by V. harveyi during its long-term persistence at elevated temperatures, we studied adaptation of this marine bacterium in sea water microcosms at 30 oC that closely mimicks the upper limits of sea surface temperatures recorded around the globe.
Project description:Members of the genus Equisetum are often referred to as “living fossils”, partly because they are the only extant representatives of the Equisetidae, a subclass that was once prominent in late Paleozoic forests. Several classes of specialized metabolites have been reported to occur in the genus Equisetum. However, while steady progress is being made with identifying individual novel metabolites of Equisetum, few if any analyses have focused on assessing the chemical diversity across the genus. The present study focused on three species: E. hyemale subsp. affine (rough horsetail or scouring rush), which is native to the temperate to artic portions of North America; E. arvense (common horsetail), which is endemic to the arctic and temperate regions of the northern hemisphere; and Equisetum telmateia subsp. braunii (Milde) Hauke (giant horsetail), which is native to western North America. Both below-ground rhizome and above-ground shoot material was harvested from each species, extracted with aqueous methanol, and subjected to non-targeted HPLC-QTOF-MS analysis. This research project was designed to lay the foundation for continued research to capture the metabolic capabilities in the ferns and fern allies.