scholarly journals Auxin regulated metabolic changes underlying sepal retention and development after pollination in spinach

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Mahpara Fatima ◽  
Xiaokai Ma ◽  
Ping Zhou ◽  
Madiha Zaynab ◽  
Ray Ming
Keyword(s):  
Auxin Transport ◽  
Differentially Expressed Gene ◽  
Metabolic Changes ◽  
Regulatory Pathways ◽  
Significant Difference ◽  
Auxin Inhibitor ◽  
Unusual Phenomenon ◽  
Auxin Transport Inhibitor ◽  
Division Cell ◽  
Early Developmental

Abstract Background Pollination accelerate sepal development that enhances plant fitness by protecting seeds in female spinach. This response requires pollination signals that result in the remodeling within the sepal cells for retention and development, but the regulatory mechanism for this response is still unclear. To investigate the early pollination-induced metabolic changes in sepal, we utilize the high-throughput RNA-seq approach. Results Spinach variety ‘Cornel 9’ was used for differentially expressed gene analysis followed by experiments of auxin analog and auxin inhibitor treatments. We first compared the candidate transcripts expressed differentially at different time points (12H, 48H, and 96H) after pollination and detected significant difference in Trp-dependent auxin biosynthesis and auxin modulation and transduction process. Furthermore, several auxin regulatory pathways i.e. cell division, cell wall expansion, and biogenesis were activated from pollination to early developmental symptoms in sepals following pollination. To further confirm the role auxin genes play in the sepal development, auxin analog (2, 4-D; IAA) and auxin transport inhibitor (NPA) with different concentrations gradient were sprayed to the spinach unpollinated and pollinated flowers, respectively. NPA treatment resulted in auxin transport weakening that led to inhibition of sepal development at concentration 0.1 and 1 mM after pollination. 2, 4-D and IAA treatment to unpollinated flowers resulted in sepal development at lower concentration but wilting at higher concentration. Conclusion We hypothesized that sepal retention and development might have associated with auxin homeostasis that regulates the sepal size by modulating associated pathways. These findings advanced the understanding of this unusual phenomenon of sepal growth instead of abscission after pollination in spinach.

scholarly journals Hanks-Type Serine/Threonine Protein Kinases and Phosphatases in Bacteria: Roles in Signaling and Adaptation to Various Environments

2018 ◽  
Vol 19 (10) ◽  
pp. 2872 ◽  
Author(s):  
Monika Janczarek ◽  
José-María Vinardell ◽  
Paulina Lipa ◽  
Magdalena Karaś
Keyword(s):  
Dna Binding ◽  
Essential Role ◽  
Current Knowledge ◽  
Response Regulator ◽  
Protein Targets ◽  
Regulatory Pathways ◽  
Translational Machinery ◽  
Signaling Systems ◽  
Cellular Processes ◽  
Division Cell

Reversible phosphorylation is a key mechanism that regulates many cellular processes in prokaryotes and eukaryotes. In prokaryotes, signal transduction includes two-component signaling systems, which involve a membrane sensor histidine kinase and a cognate DNA-binding response regulator. Several recent studies indicate that alternative regulatory pathways controlled by Hanks-type serine/threonine kinases (STKs) and serine/threonine phosphatases (STPs) also play an essential role in regulation of many different processes in bacteria, such as growth and cell division, cell wall biosynthesis, sporulation, biofilm formation, stress response, metabolic and developmental processes, as well as interactions (either pathogenic or symbiotic) with higher host organisms. Since these enzymes are not DNA-binding proteins, they exert the regulatory role via post-translational modifications of their protein targets. In this review, we summarize the current knowledge of STKs and STPs, and discuss how these enzymes mediate gene expression in prokaryotes. Many studies indicate that regulatory systems based on Hanks-type STKs and STPs play an essential role in the regulation of various cellular processes, by reversibly phosphorylating many protein targets, among them several regulatory proteins of other signaling cascades. These data show high complexity of bacterial regulatory network, in which the crosstalk between STK/STP signaling enzymes, components of TCSs, and the translational machinery occurs. In this regulation, the STK/STP systems have been proved to play important roles.

Investigation of immune microenvironment in EGFR mutant NSCLC.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e20517-e20517
Author(s):  
Yi Hu ◽  
Longgang Cui ◽  
Xiaochen Zhao ◽  
Yuezong Bai ◽  
Fan Zhang
Keyword(s):  
T Cells ◽  
Egfr Mutation ◽  
Tumor Stroma ◽  
Median Number ◽  
Egfr Mutations ◽  
Wild Type ◽  
Immune Microenvironment ◽  
Regulatory Pathways ◽  
Significant Difference ◽  
Egfr Mutant

e20517 Background: Immune checkpoint inhibitor therapy has made great achievements in NSCLC, but patients with EGFR mutations have poor efficacy with immunotherapy. Previous studies have explored the expression of PD-L1, neo-antigen, co-mutation and regulatory pathways in EGFR mutate NSCLC. This work compared the immune microenvironment of EGFR mutant and wild-type NSCLC. Methods: Patients: NSCLC. Using multi-color immunohistochemistry (multi-IHC) to evaluate the expression of 2 indicators in tumors and tumor stroma, namely CD8+ T cell and macrophage. Shapiro-Wilk was used for normality test, and t-test or Mann-Whitney U test was used according to the results. Two-sided P < 0.05 was considered a significant difference. Results: The study included 119 NSCLC patients, including 59 women (49.6%) and 60 men (50.4%), with a median age of 57. There were 68 patients (57.1%) with EGFR mutations, 19 patients (16%) with KRAS mutations, and 58 patients (48.7%) with TP53 mutations. multi-IHC results showed that, EGFR mutation Vs EGFR wild type samples, (1) the number and proportion of CD8+ T cells in tumor were not statistically different. The median number of CD8+ T cells in tumor stroma was 231.5 vs 359, p = 0.05 and the proportion of CD8+ T cells was 3.92% vs 5.64%, p = 0.02; (2) The median number of macrophage in tumors was 1522 vs 110, p < 0.01, and the proportion of macrophage cells was 24.93% Vs 1.38%, p < 0.01. The median value of macrophages in tumor stroma was 617.5 Vs 208, p < 0.01, and the proportion of macrophages cells was 10.88% vs 3.03%, p < 0.01. Conclusions: Compared with EGFR wild-type patients, EGFR mutation patients have a lower proportion of CD8+ T cells and a higher proportion of macrophages in the immune microenvironment.

Corrigendum to: Auxin is required for pollination-induced ovary growth in Dendrobium orchids

2006 ◽  
Vol 33 (10) ◽  
pp. 981 ◽  
Author(s):  
Saichol Ketsa ◽  
Apinya Wisutiamonkul ◽  
Wouter G. van Doorn
Keyword(s):  
Auxin Transport ◽  
Isobutyric Acid ◽  
Signalling Pathway ◽  
Aminooxyacetic Acid ◽  
Ethylene Synthesis ◽  
Transport Inhibitor ◽  
Auxin Signalling ◽  
Auxin Transport Inhibitor ◽  
Ethylene Action ◽  
Ovary Growth

In Dendrobium and other orchids the ovule becomes mature long after pollination, whereas the ovary starts growing within two days of pollination. The signalling pathway that induces rapid ovary growth after pollination has remained elusive. We placed the auxin antagonist �-(p-chlorophenoxy) isobutyric acid (PCIB) or the auxin transport inhibitor 2,3,5-triiodobenzoic acid (TIBA) on the stigma, before pollination. Both treatments nullified pollination-induced ovary growth. The ovaries also did not grow after similar stigma treatment with 1-methylcyclopropene (1-MCP), AgNO3 (both inhibitors of ethylene action), aminooxyacetic acid (AOA) or CoCl2 (which both inhibit ethylene synthesis), before pollination. Pollination could be replaced by placement of the auxin naphthylacetic acid (NAA) on the stigma. All mentioned inhibitors nullified the effect of NAA, indicating that if auxin is the initiator of ovary growth, it acts through ethylene. The results suggest that the pollination effect on ovary growth requires auxin (at least auxin transport and maybe also auxin signalling), and both ethylene synthesis and ethylene action.

Morphological classification of pancreatic ductal adenocarcinoma that predicts molecular subtypes and correlates with clinical outcome

Gut ◽  
2019 ◽  
Vol 69 (2) ◽  
pp. 317-328 ◽  
Author(s):  
Sangeetha N Kalimuthu ◽  
Gavin W Wilson ◽  
Robert C Grant ◽  
Matthew Seto ◽  
Grainne O’Kane ◽  
...  
Keyword(s):  
Pancreatic Ductal Adenocarcinoma ◽  
Molecular Subtypes ◽  
Differentially Expressed Gene ◽  
Biological Significance ◽  
Treatment Strategies ◽  
Ductal Adenocarcinoma ◽  
Rna Seq ◽  
Gene Signatures ◽  
Significant Difference ◽  
Morphological Patterns

IntroductionTranscriptional analyses have identified several distinct molecular subtypes in pancreatic ductal adenocarcinoma (PDAC) that have prognostic and potential therapeutic significance. However, to date, an indepth, clinicomorphological correlation of these molecular subtypes has not been performed. We sought to identify specific morphological patterns to compare with known molecular subtypes, interrogate their biological significance, and furthermore reappraise the current grading system in PDAC.DesignWe first assessed 86 primary, chemotherapy-naive PDAC resection specimens with matched RNA-Seq data for specific, reproducible morphological patterns. Differential expression was applied to the gene expression data using the morphological features. We next compared the differentially expressed gene signatures with previously published molecular subtypes. Overall survival (OS) was correlated with the morphological and molecular subtypes.ResultsWe identified four morphological patterns that segregated into two components (‘gland forming’ and ‘non-gland forming’) based on the presence/absence of well-formed glands. A morphological cut-off (≥40% ‘non-gland forming’) was established using RNA-Seq data, which identified two groups (A and B) with gene signatures that correlated with known molecular subtypes. There was a significant difference in OS between the groups. The morphological groups remained significantly prognostic within cancers that were moderately differentiated and classified as ‘classical’ using RNA-Seq.ConclusionOur study has demonstrated that PDACs can be morphologically classified into distinct and biologically relevant categories which predict known molecular subtypes. These results provide the basis for an improved taxonomy of PDAC, which may lend itself to future treatment strategies and the development of deep learning models.

scholarly journals Activation of Big Grain1 significantly improves grain size by regulating auxin transport in rice

2015 ◽  
Vol 112 (35) ◽  
pp. 11102-11107 ◽  
Author(s):  
Linchuan Liu ◽  
Hongning Tong ◽  
Yunhua Xiao ◽  
Ronghui Che ◽  
Fan Xu ◽  
...  
Keyword(s):  
Grain Size ◽  
Auxin Transport ◽  
Vascular Tissue ◽  
Plant Biomass ◽  
Key Factors ◽  
Auxin Distribution ◽  
New Strategy ◽  
Dna Insertion ◽  
Auxin Transport Inhibitor ◽  
Naphthylphthalamic Acid

Grain size is one of the key factors determining grain yield. However, it remains largely unknown how grain size is regulated by developmental signals. Here, we report the identification and characterization of a dominant mutant big grain1 (Bg1-D) that shows an extra-large grain phenotype from our rice T-DNA insertion population. Overexpression of BG1 leads to significantly increased grain size, and the severe lines exhibit obviously perturbed gravitropism. In addition, the mutant has increased sensitivities to both auxin and N-1-naphthylphthalamic acid, an auxin transport inhibitor, whereas knockdown of BG1 results in decreased sensitivities and smaller grains. Moreover, BG1 is specifically induced by auxin treatment, preferentially expresses in the vascular tissue of culms and young panicles, and encodes a novel membrane-localized protein, strongly suggesting its role in regulating auxin transport. Consistent with this finding, the mutant has increased auxin basipetal transport and altered auxin distribution, whereas the knockdown plants have decreased auxin transport. Manipulation of BG1 in both rice and Arabidopsis can enhance plant biomass, seed weight, and yield. Taking these data together, we identify a novel positive regulator of auxin response and transport in a crop plant and demonstrate its role in regulating grain size, thus illuminating a new strategy to improve plant productivity.

The white-tip nematode, Aphelenchoides besseyi, exhibits an auxin-orientated behaviour affecting its migration and propagation

Nematology ◽  
2014 ◽  
Vol 16 (7) ◽  
pp. 837-845 ◽  
Author(s):  
Hui Feng ◽  
Ying Shao ◽  
Li-hui Wei ◽  
Cun-yi Gao ◽  
Yi-jun Zhou
Keyword(s):  
Auxin Transport ◽  
Naphthaleneacetic Acid ◽  
Male Sterile ◽  
Auxin Level ◽  
Rice Plants ◽  
Transport Inhibitor ◽  
Large Numbers ◽  
Auxin Concentration ◽  
Aphelenchoides Besseyi ◽  
Auxin Transport Inhibitor

Aphelenchoides besseyi is an obligate parasite that often causes white-tip symptoms in rice plants. The nematode exhibits ectoparasitic behaviour with its infection rate matching the development of rice plants. Few studies have analysed how A. besseyi migration is influenced by chemical and host factors. Here, we focused on the effects of auxins on nematode migration and propagation. Exposure of A. besseyi to an auxin gradient created by a Pluronic F-127 gel resulted in nematode aggregation at the highest auxin concentration tested, 100 μm. Inoculation on the susceptible cv. Ningjing1 produced more nematodes than on the resistant rice cv. Tetep, which correlated with their endogenous auxin levels. Young panicles treated with 1-naphthaleneacetic acid produced more grains and nematodes, whereas plants treated with the auxin transport inhibitor, 2,3,5-triiodobenzoic acid, led to fewer nematodes in the seeds. In addition, A. besseyi rarely migrated and multiplied in the plants of the male sterile rice cv. Zhenshan97A, which had insufficient auxin level in pollen and thus could not generate any grains in most panicles. However, large numbers of nematodes were observed in seeds of cv. Zhenshan97A that had received pollens from the maintainer cv. Zhenshan97B. The results indicate that auxin might play a key role in the migration and propagation of A. besseyi.

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