scholarly journals Leaf heteroblasty in Passiflora edulis as revealed by metabolic profiling and expression analyses of the microRNAs miR156 and miR172

2019 ◽  
Vol 123 (7) ◽  
pp. 1191-1203 ◽  
Author(s):  
Priscila O Silva ◽  
Diego S Batista ◽  
João Henrique F Cavalcanti ◽  
Andréa D Koehler ◽  
Lorena M Vieira ◽  
...  

Abstract Background and Aims Juvenile-to-adult phase transition is marked by changes in leaf morphology, mostly due to the temporal development of the shoot apical meristem, a phenomenon known as heteroblasty. Sugars and microRNA-controlled modules are components of the heteroblastic process in Arabidopsis thaliana leaves. However, our understanding about their roles during phase-changing in other species, such as Passiflora edulis, remains limited. Unlike Arabidopsis, P. edulis (a semi-woody perennial climbing vine) undergoes remarkable changes in leaf morphology throughout juvenile-to-adult transition. Nonetheless, the underlying molecular mechanisms are unknown. Methods Here we evaluated the molecular mechanisms underlying the heteroblastic process by analysing the temporal expression of microRNAs and targets in leaves as well as the leaf metabolome during P. edulis development. Key Results Metabolic profiling revealed a unique composition of metabolites associated with leaf heteroblasty. Increasing levels of glucose and α-trehalose were observed during juvenile-to-adult phase transition. Accumulation of microRNA156 (miR156) correlated with juvenile leaf traits, whilst miR172 transcript accumulation was associated with leaf adult traits. Importantly, glucose may mediate adult leaf characteristics during de novo shoot organogenesis by modulating miR156-targeted PeSPL9 expression levels at early stages of shoot development. Conclusions Altogether, our results suggest that specific sugars may act as co-regulators, along with two microRNAs, leading to leaf morphological modifications throughout juvenile-to-adult phase transition in P. edulis.

2019 ◽  
Author(s):  
Yong QI ◽  
Xinzhuan YAO ◽  
Degang ZHAO ◽  
Litang Lu

Abstract Background Polyploidization has undergone a series of significant changes in the morphology and physiology of tea plants as plants multiply, especially in terms of increased growth rate and genetic gainsResult In this study, we found that the leaves of triploid tea had obvious growth advantages compared with diploid tea leaves, which was 59.81% higher than that of diploid leaves areas. The morphological structure of the triploid leaves showed obvious changes, the xylem of the veins was more developed, the cell-to-cell gap between the palisade tissue and the sponge tissue became larger, and the stomata of the triploid leaves were enlarged. After the polyploidy of tea, the content of secondary metabolites in tea leaves also changed significantly. Transcriptome sequencing analysis showed that after the triploidization of tea, the changes of leaf morphology and physiological characteristics were affected by the specific expression of some key regulatory genes. we identified a large number of transcripts and genes that might play important roles in leaf development, especially those involved in cell division, photosynthesis, hormone synthesis, and stomatal development.Conclusion This study will improve our understanding of the molecular mechanisms of tea leaf and stomatal development and provide the basis for molecular breeding of high quality and yield tea varieties. Furthermore, it gives information that may enhance understanding of triploid physiology.


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Xiaofang Jin ◽  
Dandan Liu ◽  
Linlong Ma ◽  
Ziming Gong ◽  
Dan Cao ◽  
...  

The tea plant (Camellia sinensis (L.) O. Kuntze) is an economically important woody perennial nonalcoholic health beverage crop. Tea seeds are categorized as recalcitrant and are sensitive to dehydration treatment. However, the molecular basis of this phenomenon has not been investigated. Thus, we analyzed the genome-wide expression profiles of three dehydration stages using RNA-Seq and digital gene expression (DGE) technologies. We performed de novo assembly and obtained a total of 91,925 nonredundant unigenes, of which 58,472 were extensively annotated. By a hierarchical clustering of differentially expressed genes (DEGs), we found that 8929 DEGs were downregulated and 5875 DEGs were upregulated during dehydration treatment. A series of genes related to ABA biosynthesis and signal transduction, transcription factor, antioxidant enzyme, LEA protein, and proline metabolism that have been reported to function in dehydration process were found to be downregulated. Additionally, the expression profiles of 12 selected genes related to tea seed dehydration treatment were confirmed by qRT-PCR analysis. To our knowledge, this is the first genome-wide study elucidating the possible molecular mechanisms of sensitivity of recalcitrant tea seeds to dehydration. The results obtained in this study contribute to the preservation of tea seeds as genetic resources and can also be used to explore the mechanism of dehydration sensitivity of other recalcitrant seeds.


Nature ◽  
2021 ◽  
Author(s):  
Fides Zenk ◽  
Yinxiu Zhan ◽  
Pavel Kos ◽  
Eva Löser ◽  
Nazerke Atinbayeva ◽  
...  

AbstractFundamental features of 3D genome organization are established de novo in the early embryo, including clustering of pericentromeric regions, the folding of chromosome arms and the segregation of chromosomes into active (A-) and inactive (B-) compartments. However, the molecular mechanisms that drive de novo organization remain unknown1,2. Here, by combining chromosome conformation capture (Hi-C), chromatin immunoprecipitation with high-throughput sequencing (ChIP–seq), 3D DNA fluorescence in situ hybridization (3D DNA FISH) and polymer simulations, we show that heterochromatin protein 1a (HP1a) is essential for de novo 3D genome organization during Drosophila early development. The binding of HP1a at pericentromeric heterochromatin is required to establish clustering of pericentromeric regions. Moreover, HP1a binding within chromosome arms is responsible for overall chromosome folding and has an important role in the formation of B-compartment regions. However, depletion of HP1a does not affect the A-compartment, which suggests that a different molecular mechanism segregates active chromosome regions. Our work identifies HP1a as an epigenetic regulator that is involved in establishing the global structure of the genome in the early embryo.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Ba Van Vu ◽  
Quyet Nguyen ◽  
Yuki Kondo-Takeoka ◽  
Toshiki Murata ◽  
Naoki Kadotani ◽  
...  

AbstractTransposable elements are common targets for transcriptional and post-transcriptional gene silencing in eukaryotic genomes. However, the molecular mechanisms responsible for sensing such repeated sequences in the genome remain largely unknown. Here, we show that machinery of homologous recombination (HR) and RNA silencing play cooperative roles in copy number-dependent de novo DNA methylation of the retrotransposon MAGGY in the fungusPyricularia oryzae. Genetic and physical interaction studies revealed thatRecAdomain-containing proteins, includingP. oryzaehomologs ofRad51, Rad55, andRad57, together with an uncharacterized protein, Ddnm1, form complex(es) and mediate either the overall level or the copy number-dependence of de novo MAGGY DNA methylation, likely in conjunction with DNA repair. Interestingly,P. oryzaemutants of specific RNA silencing components (MoDCL1andMoAGO2)were impaired in copy number-dependence of MAGGY methylation. Co-immunoprecipitation of MoAGO2 and HR components suggested a physical interaction between the HR and RNA silencing machinery in the process.


2021 ◽  
Vol 22 (15) ◽  
pp. 8338
Author(s):  
Asad Jan ◽  
Nádia Pereira Gonçalves ◽  
Christian Bjerggaard Vaegter ◽  
Poul Henning Jensen ◽  
Nelson Ferreira

The pathological aggregation of the presynaptic protein α-synuclein (α-syn) and propagation through synaptically coupled neuroanatomical tracts is increasingly thought to underlie the pathophysiological progression of Parkinson’s disease (PD) and related synucleinopathies. Although the precise molecular mechanisms responsible for the spreading of pathological α-syn accumulation in the CNS are not fully understood, growing evidence suggests that de novo α-syn misfolding and/or neuronal internalization of aggregated α-syn facilitates conformational templating of endogenous α-syn monomers in a mechanism reminiscent of prions. A refined understanding of the biochemical and cellular factors mediating the pathological neuron-to-neuron propagation of misfolded α-syn will potentially elucidate the etiology of PD and unravel novel targets for therapeutic intervention. Here, we discuss recent developments on the hypothesis regarding trans-synaptic propagation of α-syn pathology in the context of neuronal vulnerability and highlight the potential utility of novel experimental models of synucleinopathies.


Biology ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 576
Author(s):  
Yanru Fan ◽  
Wanfeng Li ◽  
Zhexin Li ◽  
Shaofei Dang ◽  
Suying Han ◽  
...  

The study of somatic embryogenesis can provide insight into early plant development. We previously obtained LaMIR166a-overexpressing embryonic cell lines of Larix kaempferi (Lamb.) Carr. To further elucidate the molecular mechanisms associated with miR166 in this species, the transcriptional profiles of wild-type (WT) and three LaMIR166a-overexpressing transgenic cell lines were subjected to RNA sequencing using the Illumina NovaSeq 6000 system. In total, 203,256 unigenes were generated using Trinity de novo assembly, and 2467 differentially expressed genes were obtained by comparing transgenic and WT lines. In addition, we analyzed the cleaved degree of LaMIR166a target genes LaHDZ31–34 in different transgenic cell lines by detecting the expression pattern of LaHdZ31–34, and their cleaved degree in transgenic cell lines was higher than that in WT. The downstream genes of LaHDZ31–34 were identified using Pearson correlation coefficients. Yeast one-hybrid and dual-luciferase report assays revealed that the transcription factors LaHDZ31–34 could bind to the promoters of LaPAP, LaPP1, LaZFP5, and LaPHO1. This is the first report of gene expression changes caused by LaMIR166a overexpression in Japanese larch. These findings lay a foundation for future studies on the regulatory mechanism of miR166.


Cephalalgia ◽  
2008 ◽  
Vol 28 (8) ◽  
pp. 887-891 ◽  
Author(s):  
B de Vries ◽  
AH Stam ◽  
F Beker ◽  
AMJM van den Maagdenberg ◽  
KRJ Vanmolkot ◽  
...  

Familial hemiplegic migraine (FHM) and alternating hemiplegia of childhood (AHC) are severe neurological disorders that share clinical features. Therefore, FHM genes are candidates for AHC. We performed mutation analysis in the CACNA1A gene in a monozygotic twin pair with clinical features overlapping with both AHC and FHM and identified a novel de novo CACNA1A mutation. We provide the first evidence that a CACNA1A mutation can cause atypical AHC, indicating an overlap of molecular mechanisms causing AHC and FHM. These results also suggest that CACNA1A mutation scanning is indicated in patients with a severe neurological phenotype that includes paroxysmal (alternating) hemiplegia.


2015 ◽  
Vol 172 (6) ◽  
pp. 803-811 ◽  
Author(s):  
Maya B Lodish ◽  
Bo Yuan ◽  
Isaac Levy ◽  
Glenn D Braunstein ◽  
Charalampos Lyssikatos ◽  
...  

ObjectiveWe have recently reported five patients with bilateral adrenocortical hyperplasia (BAH) and Cushing's syndrome (CS) caused by constitutive activation of the catalytic subunit of protein kinase A (PRKACA). By doing new in-depth analysis of their cytogenetic abnormality, we attempted a better genotype–phenotype correlation of theirPRKACAamplification.DesignThis study is a case series.MethodsMolecular cytogenetic, genomic, clinical, and histopathological analyses were performed in five patients with CS.ResultsReinvestigation of the defects of previously described patients by state-of-the-art molecular cytogenetics showed complex genomic rearrangements in the chromosome 19p13.2p13.12 locus, resulting in copy number gains encompassing the entirePRKACAgene; three patients (one sporadic case and two related cases) were observed with gains consistent with duplications, while two sporadic patients were observed with gains consistent with triplications. Although all five patients presented with ACTH-independent CS, the three sporadic patients had micronodular BAH and underwent bilateral adrenalectomy in early childhood, whereas the two related patients, a mother and a son, presented with macronodular BAH as adults. In at least one patient,PRKACAtriplication was associated with a more severe phenotype.ConclusionsConstitutional chromosomalPRKACAgene amplification is a recently identified genetic defect associated with CS, a trait that may be inherited in an autosomal dominant manner or occurde novo. Genomic rearrangements can be complex and can result in different copy number states of dosage-sensitive genes, e.g., duplication and triplication.PRKACAamplification can lead to variable phenotypes clinically and pathologically, both micro- and macro-nodular BAH, the latter of which we speculate may depend on the extent of amplification.


2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Liangbin Zeng ◽  
Airong Shen ◽  
Jia Chen ◽  
Zhun Yan ◽  
Touming Liu ◽  
...  

The ramie mothCocytodes coeruleaGuenée (RM) is an economically important pest that seriously impairs the yield of ramie, an important natural fiber crop. The molecular mechanisms that underlie the ramie-pest interactions are unclear up to date. Therefore, a transcriptome profiling analysis would aid in understanding the ramie defense mechanisms against RM. In this study, we first constructed two cDNA libraries derived from RM-challenged (CH) and unchallenged (CK) ramie leaves. The subsequent sequencing of the CH and CK libraries yielded 40.2 and 62.8 million reads, respectively. Furthermore,de novoassembling of these reads generated 26,759 and 29,988 unigenes, respectively. An integrated assembly of data from these two libraries resulted in 46,533 unigenes, with an average length of 845 bp per unigene. Among these genes, 24,327 (52.28%) were functionally annotated by predicted protein function. A comparative analysis of the CK and CH transcriptome profiles revealed 1,980 differentially expressed genes (DEGs), of which 750 were upregulated and 1,230 were downregulated. A quantitative real-time PCR (qRT-PCR) analysis of 13 random selected genes confirmed the gene expression patterns that were determined by Illumina sequencing. Among the DEGs, the expression patterns of transcription factors, protease inhibitors, and antioxidant enzymes were studied. Overall, these results provide useful insights into the defense mechanism of ramie against RM.


2021 ◽  
Vol 22 (18) ◽  
pp. 9874
Author(s):  
Matin Miryeganeh ◽  
Hidetoshi Saze

Their high adaptability to difficult coastal conditions makes mangrove trees a valuable resource and an interesting model system for understanding the molecular mechanisms underlying stress tolerance and adaptation of plants to the stressful environmental conditions. In this study, we used RNA sequencing (RNA-Seq) for de novo assembling and characterizing the Bruguiera gymnorhiza (L.) Lamk leaf transcriptome. B. gymnorhiza is one of the most widely distributed mangrove species from the biggest family of mangroves; Rhizophoraceae. The de novo assembly was followed by functional annotations and identification of individual transcripts and gene families that are involved in abiotic stress response. We then compared the genome-wide expression profiles between two populations of B. gymnorhiza, growing under different levels of stress, in their natural habitats. One population living in high salinity environment, in the shore of the Pacific Ocean- Japan, and the other population living about one kilometre farther from the ocean, and next to the estuary of a river; in less saline and more brackish condition. Many genes involved in response to salt and osmotic stress, showed elevated expression levels in trees growing next to the ocean in high salinity condition. Validation of these genes may contribute to future salt-resistance research in mangroves and other woody plants. Furthermore, the sequences and transcriptome data provided in this study are valuable scientific resources for future comparative transcriptome research in plants growing under stressful conditions.


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