scholarly journals YUCCA-Mediated Biosynthesis of the Auxin IAA Is Required during the Somatic Embryogenic Induction Process in Coffea canephora

2020 ◽  
Vol 21 (13) ◽  
pp. 4751
Author(s):  
Miguel A. Uc-Chuc ◽  
Cleyre Pérez-Hernández ◽  
Rosa M. Galaz-Ávalos ◽  
Ligia Brito-Argaez ◽  
Víctor Aguilar-Hernández ◽  
...  
Keyword(s):  
De Novo ◽  
Leaf Explants ◽  
Coffea Canephora ◽  
Naphthaleneacetic Acid ◽  
Induction Process ◽  
Exogenous Addition ◽  
Pre Treatment ◽  
Process Of Se ◽  
Somatic Embryogenic ◽  
Indole 3 Acetic Acid

Despite the existence of considerable research on somatic embryogenesis (SE), the molecular mechanism that regulates the biosynthesis of auxins during the SE induction process remains unknown. Indole-3-acetic acid (IAA) is an auxin that is synthesized in plants through five pathways. The biosynthetic pathway most frequently used in this synthesis is the conversion of tryptophan to indol-3-pyruvic acid (IPA) by tryptophan aminotransferase of Arabidopsis (TAA) followed by the conversion of IPA to IAA by enzymes encoded by YUCCA (YUC) genes of the flavin monooxygenase family; however, it is unclear whether YUC-mediated IAA biosynthesis is involved in SE induction. In this study, we report that the increase of IAA observed during SE pre-treatment (plants in MS medium supplemented with 1-naphthaleneacetic acid (NAA) 0.54 µM and kinetin (Kin) 2.32 µM for 14 days) was due to its de novo biosynthesis. By qRT-PCR, we demonstrated that YUC gene expression was consistent with the free IAA signal found in the explants during the induction of SE. In addition, the use of yucasin to inhibit the activity of YUC enzymes reduced the signal of free IAA in the leaf explants and dramatically decreased the induction of SE. The exogenous addition of IAA restored the SE process in explants treated with yucasin. Our findings suggest that the biosynthesis and localization of IAA play an essential role during the induction process of SE in Coffea canephora.

scholarly journals Long-Term Waterlogging as Factor Contributing to Hypoxia Stress Tolerance Enhancement in Cucumber: Comparative Transcriptome Analysis of Waterlogging Sensitive and Tolerant Accessions

Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 189
Author(s):  
Kinga Kęska ◽  
Michał Wojciech Szcześniak ◽  
Izabela Makałowska ◽  
Małgorzata Czernicka
Keyword(s):  
Stress Tolerance ◽  
De Novo ◽  
Average Length ◽  
Marker Genes ◽  
Long Term Memory ◽  
Low Oxygen ◽  
Waterlogging Tolerance ◽  
Pre Treatment ◽  
Waterlogging Treatment

Waterlogging (WL), excess water in the soil, is a phenomenon often occurring during plant cultivation causing low oxygen levels (hypoxia) in the soil. The aim of this study was to identify candidate genes involved in long-term waterlogging tolerance in cucumber using RNA sequencing. Here, we also determined how waterlogging pre-treatment (priming) influenced long-term memory in WL tolerant (WL-T) and WL sensitive (WL-S) i.e., DH2 and DH4 accessions, respectively. This work uncovered various differentially expressed genes (DEGs) activated in the long-term recovery in both accessions. De novo assembly generated 36,712 transcripts with an average length of 2236 bp. The results revealed that long-term waterlogging had divergent impacts on gene expression in WL-T DH2 and WL-S DH4 cucumber accessions: after 7 days of waterlogging, more DEGs in comparison to control conditions were identified in WL-S DH4 (8927) than in WL-T DH2 (5957). Additionally, 11,619 and 5007 DEGs were identified after a second waterlogging treatment in the WL-S and WL-T accessions, respectively. We identified genes associated with WL in cucumber that were especially related to enhanced glycolysis, adventitious roots development, and amino acid metabolism. qRT-PCR assay for hypoxia marker genes i.e., alcohol dehydrogenase (adh), 1-aminocyclopropane-1-carboxylate oxidase (aco) and long chain acyl-CoA synthetase 6 (lacs6) confirmed differences in response to waterlogging stress between sensitive and tolerant cucumbers and effectiveness of priming to enhance stress tolerance.

scholarly journals In vitro shoot regeneration of boldo from leaf explants

2010 ◽  
Vol 40 (10) ◽  
pp. 2210-2213
Author(s):  
Monalize Salete Mota ◽  
Juliana de Magalhães Bandeira ◽  
Eugenia Jacira Bolacel Braga ◽  
Valmor João Bianchi ◽  
José Antonio Peters
Keyword(s):  
Shoot Regeneration ◽  
Leaf Explants ◽  
Shoot Development ◽  
High Potential ◽  
Naphthaleneacetic Acid ◽  
Regeneration System ◽  
Bud Induction ◽  
Molecular Studies ◽  
In Vitro Shoot Regeneration

A shoot regeneration system for Plectranthus neochilus was studied from leaf explants. Leaves developed under in vitro conditions were cultured on Wood Plant Medium supplemented with 0.2mg dm-3 α-naphthaleneacetic acid (NAA) and different 6-benzilaminopurine (BAP) or thidiazuron (TDZ) concentrations (0, 1.5, 3.0, 4.5 and 6.0mg dm-3). An increase in percentage of responsive explants (85.3%) and in the number of shoots developed per explant (3.2) was observed when the explants were treated with 5.3 and 4.7mg dm-3 BAP, respectively. The leaf explants cultured on media supplemented with TDZ became vitreous and did not form buds. The regeneration system used is efficient for boldo bud induction and shoot development, showing high potential for advanced cellular and molecular studies.

Effect of auxin and phenobarbital on the ultrastructure and digitoxin content in Digitalis purpurea tissue culture

1996 ◽  
Vol 74 (3) ◽  
pp. 378-382 ◽  
Author(s):  
Mercedes Bonfill ◽  
Javier Palazón ◽  
Rosa M. Cusidó ◽  
M. Teresa Piñol ◽  
Carmen Morales
Keyword(s):  
Acetic Acid ◽  
Volume Fraction ◽  
Volume Ratio ◽  
Naphthaleneacetic Acid ◽  
Acetic Acid Medium ◽  
Digitalis Purpurea ◽  
Murashige Skoog ◽  
Mitochondrial Volume ◽  
Callus Tissues ◽  
Indole 3 Acetic Acid

Callus derived from Digitalis purpurea hypocotils were grown during a 6-week period on solid Murashige–Skoog medium supplemented with 1 mg/L 6-benzylaminopurine, 0.01 mg/L gibberellic acid and 0.1 mg/L indole-3-acetic acid or α-naphthaleneacetic acid, with or without phenobarbital (40 mg/L). The presence of phenobarbital in the culture medium caused a reduction of the vacuole/cytoplasm ratio. At the same time, the chloroplastic volume fraction decreased in callus tissue cells grown in media supplemented with phenobarbital, while the mitochondrial volume ratio increased. Digitoxin content was enhanced in callus tissues, especially in those grown on indole-3-acetic acid medium supplemented with phenobarbital. The relationship between ultrastructure of D. purpurea callus and digitoxin content is discussed. Keywords: Digitalis purpurea tissue cultures, digitoxin, phenobarbital, mitochondria, chloroplast.

The combination of EGFR-TKIs and anlotinib as a first-line therapy for EGFR-mutant advanced non-small cell lung cancer: A multicenter, single-arm, phase II clinical trial.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 9030-9030
Author(s):  
Zhiyong He ◽  
Jinghui Lin ◽  
Yueming He ◽  
Jing Zhang ◽  
Dongyong Yang ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Adverse Events ◽  
Advanced Nsclc ◽  
De Novo ◽  
Egfr Mutations ◽  
Treatment Naïve ◽  
Pre Treatment ◽  
Egfr Mutant ◽  
Nsclc Patients ◽  
Egfr Tkis

9030 Background: Currently,EGFR-TKIs are widely accepted as the standard treatment for EGFR- mutant advanced non-small-cell lung cancer (NSCLC); however, acquired resistance is inevitable. Combination therapy is considered as a strategy to overcome the resistance to EGFR-TKIs. Anlotinib, a novel multi-targeting, small-molecule TKI, has shown active to suppress tumor angiogenesis and growth. However, there is still a lack of evidence supporting the use of EGFR-TKIs in combination with anlotinib for the treatment of NSCLC until now. A multi-center, single-arm, phase II clinical trial was therefore designed to examine the efficacy and safety of EGFR-TKIs combined with anlotinib for treatment-naïve, advanced NSCLC patients, and unravel the possible mechanisms. Methods: This study was conducted in 14 research centers in Fujian, China. The main eligibility criteria were stage IV or relapsed nonsquamous NSCLC with EGFR mutations (exon 19 deletion,, and L858R), ECOG score 0-2,and age 20 to 75 years and no previous systemic treatment. Patients with asymptomatic brain metastases were admitted.Eligible patients were given gefitinib (250 mg QD) or icotinib (125 mg TID) in combination with anlotinib (10 mg per day, on days 1‒14; 21 days per cycle) until disease progression. The primary endpoint is progression-free survival (PFS) and safety, and the secondary endpoint is overall survival (OS), objective response rate (ORR) and disease control rate (DCR).Peripheral blood was sampled pre-treatment, once every two months during treatment and after disease progression, and T790M mutation was detected in plasma ctDNA using a droplet digital PCR (ddPCR) assay. Results: Of 60 patients enrolled (August 2, 2018 to May 28, 2020). As of February 1, 2021, 37 patients (61.7%) experienced PFS events and 10 (16.7%) died. The ORR was 78.3%, and the DCR was100%.Median PFS was 13.0 months (95%CI,10.7-15.3).The 5 most common treatment-related adverse events included rash (63.3%), fatigue (55.0%), hypertension (48.3%), diarrhea (33.3%) and hand-foot syndrome (30.0%), and grade 3 adverse events included hypertension (5.0%), rash (1.67%), hypertriglyceridemia (1.67%), vomiting (1.67%) and elevated ALT (1.67%); no grade 4 adverse events or drug-related deaths were observed. Peripheral blood samples were collected from 36 patients pre-treatment, and 30.6% were identified with low-frequency de novo T790M mutations, with the mutation-allele frequency (MAF) ranging from 0.01% to 0.28%. Conclusions: The combination of the first-generation EGFR-TKIs and anlotinib shows impressive ORR and DCR, and acceptable toxicity in treatment-naïve advanced NSCLC patients with activating EGFR mutations, and we observed a high proportion of patients harboring de novo EGFR T790M mutations in this study. Clinical trial information: NCT03720873.

scholarly journals Molecular Basis for Natural Vegetative Propagation via Regeneration in North American Lake Cress, Rorippa aquatica (Brassicaceae)

2019 ◽  
Vol 61 (2) ◽  
pp. 353-369 ◽  
Author(s):  
Rumi Amano ◽  
Hokuto Nakayama ◽  
Risa Momoi ◽  
Emi Omata ◽  
Shizuka Gunji ◽  
...  
Keyword(s):  
Shoot Regeneration ◽  
Vegetative Propagation ◽  
Molecular Basis ◽  
Auxin Transport ◽  
Vascular Tissue ◽  
De Novo ◽  
Leaf Explants ◽  
Experimental Models ◽  
Polar Auxin Transport ◽  
Proximal Side

Abstract Some plant species have a striking capacity for regeneration in nature, including regeneration of the entire individual from explants. However, due to the lack of suitable experimental models, the regulatory mechanisms of spontaneous whole plant regeneration are mostly unknown. In this study, we established a novel model system to study these mechanisms using an amphibious plant within Brassicaceae, Rorippa aquatica, which naturally undergoes vegetative propagation via regeneration from leaf fragments. Morphological and anatomical observation showed that both de novo root and shoot organogenesis occurred from the proximal side of the cut edge transversely with leaf vascular tissue. Time-series RNA-seq analysis revealed that auxin and cytokinin responses were activated after leaf amputation and that regeneration-related genes were upregulated mainly on the proximal side of the leaf explants. Accordingly, we found that both auxin and cytokinin accumulated on the proximal side. Application of a polar auxin transport inhibitor retarded root and shoot regeneration, suggesting that the enhancement of auxin responses caused by polar auxin transport enhanced de novo organogenesis at the proximal wound site. Exogenous phytohormone and inhibitor applications further demonstrated that, in R. aquatica, both auxin and gibberellin are required for root regeneration, whereas cytokinin is important for shoot regeneration. Our results provide a molecular basis for vegetative propagation via de novo organogenesis.

scholarly journals Efficiency of SSR markers for determining the origin of melon plantlets derived through unfertilized ovary culture

2011 ◽  
Vol 38 (No. 1) ◽  
pp. 27-34 ◽  
Author(s):  
A.A. Malik ◽  
Cui Li ◽  
Zhang Shuxia ◽  
Chen Jin-feng
Keyword(s):  
Ssr Markers ◽  
Doubled Haploids ◽  
Parent Material ◽  
Plant Production ◽  
Induction Medium ◽  
Naphthaleneacetic Acid ◽  
Heterozygous Parent ◽  
Pre Treatment ◽  
Homozygous Diploid

The effects of temperature pre-treatment, thidiazuron, naphthaleneacetic acid, and 6-benzylaminopurine on in vitro gynogenic plant production from un-pollinated melon (Cucumis melo L.) ovaries were investigated. Simple sequence repeat (SSR) marker analysis was conducted to identify the homozygous diploid individuals. The temperature pre-treatment (4°C) for 4 days increased embryo formation frequency (63.3%) significantly. Addition of thidiazuron (0.04 and 0.02 mg/l) in the induction medium significantly increased the number of responding ovaries (46.6%, 65.83%), respectively. The maximum number of plantlet regeneration (22.5%) was achieved by culturing the ovary derived embryos on Murashigue and Skoog medium (MS medium) supplement with 0.6 mg/l 6-benzylaminopurine. Spontaneous doubled haploids originated directly through embryogenesis were subjected to genetic analysis using SSR molecular marker with 23 primers pair for homozygosity. SSR markers with microsatellite CMGA172, confirmed that the alleles in the parental material were also present in the gynogenic plantlets, but amplified only two alleles as compared to four alleles of the heterozygous parent material at same locus. Therefore these regenerated plantlets were consider homozygous and produced through a process of gametophytic embryogenesis.

scholarly journals CURBING ACTINOMYCETES AND THIDIAZURON ENHANCED MICROPROPAGATION IN THE RARE ALPINIA GALANGA - A MEDICINAL ZINGIBER

2017 ◽  
Vol 10 (7) ◽  
pp. 153
Author(s):  
Baradwaj Rg ◽  
Rao Mv ◽  
Senthil Kumar T
Keyword(s):  
Fusidic Acid ◽  
Inter Simple Sequence Repeat ◽  
Mercury Chloride ◽  
Naphthaleneacetic Acid ◽  
Ms Medium ◽  
Endophytic Actinomycetes ◽  
Alpinia Galanga ◽  
First Report ◽  
Rhizome Bud ◽  
Pre Treatment

Objective: Elimination of endophytic actinomycetes before micropropagation using antibiotic pre-treatment in rhizome bud explants of Alpinia galanga. Then, the formulation of an operative protocol for Micropropagation of the same void of endophytic actinomycetes. Methods: A treatment of mercury chloride and carbendazim, alone and in combination was used as surface sterilants. A pre-treatment of rifampicin and fusidic acid was used against actinomycete endophyte disinfection of rhizome bud explants. Then, Murashige and Skoog (MS) medium supplemented with various concentrations of cytokinins were used for micropropagation of disinfected explants. Results: A treatment of 0.1% (w/v) mercury chloride and 0.1% (w/v) carbendazim, one after the other for 5 minutes gave the best sterility of 83.3%. A pre-treatment of Rifampicin 100 mg/l and fusidic acid 100 mg/l for 2 hrs gave the best disinfection of 70% against actinomycete endophytes. A combination of thidiazuron (TDZ) 0.45 μM and 6-benzyladenine 13.32 μM in MS medium resulted in 9.4 shoots per explant. MS medium fortified with 10.74 μMof 1-naphthaleneacetic acid gave the best rooting of 20 roots/shoot. inter simple sequence repeat marker genetic similarity of regenerants with the mother plant was confirmed. Conclusion: This study shows the potency of Rifampicin and Fusidic acid to disinfect explants from actinomycete endophytes and is significant as the first report on curbing actinomycetes endophytes in plant tissue culture of A. galanga. This is also the first report conferring the dissimilar regeneration capabilities of TDZ in comparison to other cytokinins in Zingiberaceae.

scholarly journals Effects of Different Colored LEDs on the Enhancement of Biologically Active Ingredients in Callus Cultures of Gynura procumbens (Lour.) Merr.

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4336 ◽  
Author(s):  
Thang Tung Lian ◽  
Se-Yeoun Cha ◽  
Myat Myat Moe ◽  
Yong Ju Kim ◽  
Keuk Soo Bang
Keyword(s):  
Liquid Chromatography ◽  
High Performance ◽  
Leaf Explants ◽  
Callus Cultures ◽  
Biologically Active ◽  
Naphthaleneacetic Acid ◽  
Light Sources ◽  
Light Emitting ◽  
Fluorescent Lamps ◽  
Wavelength Emission

Conventional fluorescent lamps that are used in tissue culture are costly light sources, exhibiting excessive wavelength emission-bandwidth that must be replaced by alternative, less costly, and much lower power-consuming energy sources. The use of Light-Emitting Diodes (LEDs) is the best option due to their potential role as elicitors of secondary metabolite production in many plant models. Gynura procumbens (G. procumbens) is widely used for treating various diseases. Here, leaf explants were cultivated in MS medium that was supplemented with 0.5 mg/L of naphthaleneacetic acid (NAA) and 2.0 mg/L of benzylaminopurine (BAP) for 30 days under white, blue, and red LEDs. Secondary metabolites were analyzed by High Performance Liquid Chromatography (HPLC) and Liquid Chromatography-Mass Spectrometry (LC-MS). Blue LEDs elicited the highest antioxidant activity, total flavonoid, and phenolic content. Furthermore, the content of cyanidin-monoglucosides significantly increased under blue light.

scholarly journals In vitro callus induction of gerbera from leaf explant

2020 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Sadia Afrin Jui ◽  
Md. Mijanur Rahman Rajib ◽  
M. Mofazzal Hossain ◽  
Sharmila Rani Mallik ◽  
Iffat Jahan Nur ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Growth Regulators ◽  
Callus Induction ◽  
Leaf Explants ◽  
Leaf Explant ◽  
Naphthalene Acetic Acid ◽  
Dichlorophenoxyacetic Acid ◽  
Ms Medium ◽  
Indole 3 Acetic Acid

The experiment was designed to evaluate the effect of growth regulators on leaf explant of Gerbera for callus induction. Various kinds of plant growth regulators such as 6-Benzylaminopurine (BAP), α-Naphthalene acetic acid (NAA), 2, 4-Dichlorophenoxyacetic acid (2, 4-D), Indole-3-acetic acid (IAA) were used to initiate cultures. These were added to Murashige and Skoog medium in different combinations and concentrations. Leaf explants cultured on MS medium supplemented with BAP+ 2, 4-D+ IAA in T4 treatment & BAP+ 2,4-D in T5 treatment showed the best results for callus induction. On the other hand callus was induced early in the combination of BA+ 2,4-D + IAA hormone in T5, T9 & T8 treatment respectively. The rate of callus induction was very low in BA + NAA combinations but it was much earlier.   

scholarly journals Establishment of a Rapid and Efficient Micropropagation System for Succulent Plant Haworthia turgida Haw.

HortScience ◽  
2017 ◽  
Vol 52 (9) ◽  
pp. 1278-1282 ◽  
Author(s):  
Boling Liu ◽  
Hongzhou Fang ◽  
Chaorong Meng ◽  
Ming Chen ◽  
Qingdong Chai ◽  
...  
Keyword(s):  
Callus Induction ◽  
Adventitious Shoots ◽  
Germplasm Conservation ◽  
Leaf Explants ◽  
Adventitious Shoot ◽  
Induction Medium ◽  
Naphthaleneacetic Acid ◽  
Root Induction ◽  
Ms Medium ◽  
Succulent Plant

In the present study, the effect of plant growth regulators (PGRs) on callus regeneration, adventitious shoot differentiation, and root formation of Haworthia turgida Haw. was investigated. The greatest callus induction percentage (95.6%) was achieved with leaf explants inoculated on Murashige and Skoog (MS) medium with 1.0 mg·L−1 6-benzyladenine (BA) and 0.1 mg·L−1 1-naphthaleneacetic acid (NAA), and this callus induction medium supplemented with 2.5 mg·L−1 thidiazuron (TDZ) was optimal for callus proliferation. The maximum number of shoots (25.7) was obtained when the callus was cultured on MS medium supplemented with 1.0 mg·L−1 BA and 0.2 mg·L−1 2,4-dichlorophenoxyacetic acid (2,4-D). The highest number of roots per shoot (6.2) and highest rooting frequency (82.0%) were obtained when adventitious shoots were inoculated on MS medium with 0.05 mg·L−1 NAA. Regenerated plantlets were transferred to a mixture of vermiculite and soil and acclimated in a greenhouse. The survival rate of the transplanted plantlets was about 91.6%. The rate of ex vitro rooting was 83.3%, indicating that this technique is effective for root induction in H. turgida. This study has established a rapid and efficient micropropagation system that can be beneficial for commercial cultivation and germplasm conservation of H. turgida.

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