Abstract
Rosa rugosa
, commonly known as rugged rose, is a perennial ornamental shrub. It produces beautiful flowers with a mild fragrance and colorful seed pods. Unlike many other cultivated roses,
...R. rugosa
adapts to a wide range of habitat types and harsh environmental conditions such as salinity, alkaline, shade, drought, high humidity, and frigid temperatures. Here, we produced and analyzed a high-quality genome sequence for
R. rugosa
to understand its ecology, floral characteristics and evolution. PacBio HiFi reads were initially used to construct the draft genome of
R. rugosa
, and then Hi-C sequencing was applied to assemble the contigs into 7 chromosomes. We obtained a 382.6 Mb genome encoding 39,704 protein-coding genes. The genome of
R. rugosa
appears to be conserved with no additional whole-genome duplication after the gamma whole-genome triplication (WGT), which occurred ~100 million years ago in the ancestor of core eudicots. Based on a comparative analysis of the high-quality genome assembly of
R. rugosa
and other high-quality Rosaceae genomes, we found a unique large inverted segment in the Chinese rose
R. chinensis
and a retroposition in strawberry caused by post-WGT events. We also found that floral development- and stress response signaling-related gene modules were retained after the WGT. Two
MADS-box
genes involved in floral development and the stress-related transcription factors
DREB2A-INTERACTING PROTEIN 2
(
DRIP2
) and
PEPTIDE TRANSPORTER 3
(
PTR3
) were found to be positively selected in evolution, which may have contributed to the unique ability of this plant to adapt to harsh environments. In summary, the high-quality genome sequence of
R. rugosa
provides a map for genetic studies and molecular breeding of this plant and enables comparative genomic studies of
Rosa
in the near future.
•Multiple transcriptome data were integrated to select candidate reference genes.•TIF3H1 was the most suitable reference gene for the self-incompatibility study of C. oleifera.•The accurate ...quantification of pectin methylesterase highlighted its role in self-incompatibility.
Self-incompatibility (SI) is one of the main reasons leading to the low fruit set of Camellia oleifera and limiting the yield of Camellia oil. It is important to uncover the molecular mechanism of SI for guiding production. Accurate quantification of the expression level of SI determinants is essential, which requires qRT-PCR technology and appropriate reference genes. However, the screening of SI-related reference genes in C. oleifera has not been reported. In this study, multiple transcriptome data were innovatively integrated and candidate reference genes of SI were systematically and rapidly screened in C. oleifera. TIF3H1 was selected as the most stable gene expressed in pistillate tissues of C. oleifera under different pollination treatments based on the comprehensive evaluation using qRT-PCR and statistical algorithms of geNorm, NormFinder, BestKeeper, and RefFinder. The expression of SI-related genes of C. oleifera validated the stability of TIF3H1 as the reference gene. Using TIF3H1 as the reference gene, the expression of the potential SI determinants in compatible and incompatible pistils was accurately quantified, and the high expression of the homologous gene of pectin methylesterase (PME) in incompatible pistils suggested its positive effect on SI of C. oleifera. The identification of TIF3H1 as the reliable reference gene guarantees more accurate qRT-PCR quantification for the study of the SI of C. oleifera, laying a foundation for identifying determinants of SI and exploring its molecular mechanism.
Abstract Phenylphenalenones (PhPNs), phytoalexins in wild bananas (Musaceae), are known to act against various pathogens. However, the abundance of PhPNs in many Musaceae plants of economic ...importance is low. Knowledge of the biosynthesis of PhPNs and the application of biosynthetic approaches to improve their yield is vital for fighting banana diseases. However, the processes of PhPN biosynthesis, especially those involved in methylation modification, remain unclear. Musella lasiocarpa is a herbaceous plant belonging to Musaceae, and due to the abundant PhPNs, their biosynthesis in M. lasiocarpa has been the subject of much attention. In this study, we assembled a telomere-to-telomere gapless genome of M. lasiocarpa as the reference, and further integrated transcriptomic and metabolomic data to mine the candidate genes involved in PhPN biosynthesis. To elucidate the diversity of PhPNs in M. lasiocarpa, three screened O-methyltransferases (Ml01G0494, Ml04G2958, and Ml08G0855) by phylogenetic and expressional clues were subjected to in vitro enzymatic assays. The results show that the three were all novel O-methyltransferases involved in the biosynthesis of PhPN phytoalexins, among which Ml08G0855 was proved to function as a multifunctional enzyme targeting multiple hydroxyl groups in PhPN structure. Moreover, we tested the antifungal activity of PhPNs against Fusarium oxysporum and found that the methylated modification of PhPNs enhanced their antifungal activity. These findings provide valuable genetic resources in banana breeding and lay a foundation for improving disease resistance through molecular breeding.
As a new type of pollutant, microplastics have attracted increased attention because of their widespread and persistent existence in the water environment. In this study, we investigated one of the ...eight largest lakes in China—Wuliangsuhai Lake in Inner Mongolia. The microplastic concentration in Wuliangsuhai Lake ranges from 3.12 to 11.25 n/L. The different functional areas in Wuliangsuhai can be divided into four categories, namely effluent, fishing, intake and wetland areas. The highest microplastic concentration occurs in the intake area. The collected microplastics are divided into four types, i.e., fibers, pellets, fragments and films, of which fibers are the most abundant. Among the four functional areas of Wuliangsuhai Lake, the highest fiber concentration is observed in the fishing area. The microplastics in Wuliangsuhai Lake are mainly small size, and the microplastics smaller than 2 mm account for 98.2% of the total microplastics, while the microplastic size in the intake area is relatively large. Polystyrene and polyethylene are the main polymer types. Agricultural wastewater, domestic sewage and fishery discharge have the greatest impact on the microplastic distribution. This study reveals that the inland lakes in northern China are polluted by microplastics, which may cause potential harm to the surrounding environment.
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•Microplastics occurrence in Wuliangsuhai Lake were investigated.•The dominant microplastics were polystyrene fiber with 0–2 mm in size.•The discharge of human sewage and industrial wastewater were the main source of microplastics.•The spatial distribution of microplastics varies between different functional areas.
To explore whether the paraventricular nucleus (PVN) participates in regulation of the anti-myocardial ischemia-reperfusion injury (MIRI) effect of electroacupuncture (EA) and whether this is ...achieved through the PVN-interposed nucleus (IN) neural pathway.
The modeling method of myocardial ischemia reperfusion injury was achieved by ligating the left anterior descending coronary artery in Sprague-Dawley rats. We used the Powerlab multi-channel physiological recorder system to record electro-cardiograms and analyze the changes in ST segment displacement; 2,3,5-Triphenyltetrazolium chloride staining was used to observe the percentage of myocardial infarction areas. Detecting cardiac troponin I (cTnI), lactate dehydrogenase (LDH) in serum was done with an enzyme-linked immunosorbent assay kit. Morphological changes in the myocardium were detected in each group with hematoxylin-eosin staining of paraffin sections. Detection of c-fos protein expression in the PVN of the hypothalamus was done with the immune-ofluorescence method. The Plexon multi-channel acquisition system recorded PVN neuron discharges and local field potentials in each group of rats. Offline Sorter software was used for cluster analysis. Neuro Explorer software was used to perform autocorrelation, raster and frequency characteristics and spectral energy analysis of neuron signals in each group.
Compared with the MIRI model group, the areas of myocardial infarction in the EA group were significantly reduced; the expression of cTnI, LDH in serum was decreased significantly. The firing frequency of pyramidal cells in the PVN was significantly increased and the spectrum energy map showed energy was reduced, c-fos expression in PVN was reduced, this indicated that neuronal activity in the PVN participates in the effect of EA improving myocardial injury. In addition, we used the kainic acid method to lesion the IN and observed that the effect of EA was weakened. For example, the area of myocardial infarction of lesion IN + EA group in rats was significantly increased compared with that resulting from EA group, the expression of cTnI, LDH in serum was significantly increased, the firing frequency of pyramidal cells in the PVN was significantly reduced. A spectral energy diagram shows that the energy after damage was higher than that of EA group. At the same time, the expression of c-fos in the PVN increased again.
Our results indicated that the PVN-IN nerve pathway may participate as an effective pathway of EA to improve the effect of myocardial injury.
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