scholarly journals Early Sucrose Degradation and the Dominant Sucrose Cleavage Pattern Influence Lycoris sprengeri Bulblet Regeneration In Vitro

2021 ◽  
Vol 22 (21) ◽  
pp. 11890
Author(s):  
Ziming Ren ◽  
Yunchen Xu ◽  
Xuesi Lvy ◽  
Dong Zhang ◽  
Cong Gao ◽  
...  

Bulblet formation and development determine the quantitative and qualitative traits, respectively, of bulb yield for most flowering bulbs. For Lycoris species, however, the underlying molecular mechanism remains elusive. Here, clonal bulblets of Lycoris sprengeri (Ls) derived from the same probulb were used as explants to establish efficient and inefficient in vitro regeneration systems by adjusting the 6-benzyladenine (BA) concentrations in media. BA application did not change the biological processes among groups but led to earlier decreases in sucrose and total soluble sugar (TSS) contents. Correlation analyses showed that the BA treatments changed the interaction between carbohydrate and endogenous hormone contents during bulblet regeneration. We found that two sucrose degradation enzyme-related genes, cell wall invertase (CWIN) and sucrose synthase, exhibited exactly opposite expression patterns during the competence stage. In addition, the regeneration system that obtained more bulblets showed significantly higher expression of LsCWIN2 than those that obtained fewer bulblets. Our data demonstrate the essential role of BA in accelerating sucrose degradation and the selection of a dominant sucrose cleavage pattern at the competence stage of in vitro bulblet regeneration. We propose that a relatively active CWIN-catalyzed pathway at the competence stage might promote bulblet regeneration, thus influencing bulb yield.

2016 ◽  
Vol 86 ◽  
pp. 49-57 ◽  
Author(s):  
Jannette Alonso-Herrada ◽  
Félix Rico-Reséndiz ◽  
Juan Campos-Guillén ◽  
Ramón G. Guevara-González ◽  
Irineo Torres-Pacheco ◽  
...  

2021 ◽  
Vol 17 (5) ◽  
pp. 495-503
Author(s):  
Shamsiah Abdullah ◽  
Siti Nurain Roslan

One of the challenges related to propagation of Arenga pinnata is its lengthy period of seed dormancy. In this study, in vitro regeneration was carried out to determine the effect of hormonal treatment on the embryo explant of Arenga pinnata. Embryos were surface sterilized and cultured into different media supplemented with various hormones concentrations and combinations. Each treatment contained of Kinetin (KN) hormone (1.0, 2.0, and 3.0 mg/l) and in combination with indole-3-acetic acid (IAA) of 0.1, 0.2, 0.3 mg/l. The height of plumule and length of radical was observed and recorded. Treatment 8 (3 mg/ml KN + 0.1 mg/ml IAA) showed 59.09% in plumule height increment while treatment 4 (1 mg/ml KN + 0.3 mg/ml IAA) showed the highest radical increments with 93.62%. The knowledge gained in this study consequently helps us to better understand the role of KN and IAA in the in vitro regeneration protocol. Since in vitro method able to produce higher number of in vitro seedlings at one time, it is important to establish the in vitro regeneration protocol for this plant.


2021 ◽  
Author(s):  
Maddalena del Gallo ◽  
Amedeo Mignini ◽  
Giulio Moretti ◽  
Marika Pellegrini ◽  
Paola Cacchio

<p>CO<sub>2</sub> emissions triggered by anthropogenic and natural activities contribute to climate change, one of the current environmental threats of public and scientific concern. At present, microbially-induced biomineralization of CO<sub>2</sub> by calcium carbonate (CaCO<sub>3</sub>) is one of the highly topical study subjects as carbon stabilization process. In the present study we focused our attention on the calcifying bacteria of “living rocks”. The origin of these concretions, composed by a silicate skeleton of quartz and feldspars, merged by massive carbonate concrete, has so far been recognized as abiotic. Within this study we investigated the role of calcifying bacteria in their formation of these concretions and we isolated and characterized the species with CaCO<sub>3</sub> precipitation abilities. Concretions were sampled in Romania (Trovant) and Italy (Sibari and Rome). Samples were first analyzed for their culturable microflora (i.e. isolation, CaCO<sub>3 </sub>precipitation capability and molecular characterization). Then, in vitro regeneration tests were carried out to confirm the contribution of bacteria in the formation of these erratic masses. Moreover, natural samples and bioliths regenerated in vitro were (i) observed and analyzed by scanning electron microscopy (SEM-EDS) and (ii) characterized at molecular level by DNA extraction and 16S rRNA analysis (V3-V4 regions). By isolating and characterizing the culturable microflora, we obtained 19 calcifying isolates, with different morphological, bacteriological and mineral precipitation properties. These evidences have given a first relevant contribution for the definition of the biotic role to the formation of these concretions. These evidences were confirmed by the efficient in vitro regeneration and SEM-EDS analysis. The molecular identification of the isolates and the comparison of the data obtained from the Illumina sequencing with those present in the literature, allowed us to hypothesize the genera that most likely contributed to the formation of these concretions. The results obtained provide a good scientific basis for further studies, which should be directed towards the use of isolates in studies of environmental and socio-economic relevance. Several studies demonstrate that microbially mediated biomineralization has the potential to capture and sequester carbon. Calcium carbonate, is a stable pool of carbon and is an effective sealant to prevent CO<sub>2</sub> release back into the atmosphere.</p>


Development ◽  
2001 ◽  
Vol 128 (6) ◽  
pp. 895-906
Author(s):  
B. Knoll ◽  
K. Zarbalis ◽  
W. Wurst ◽  
U. Drescher

We have investigated the role of the Eph family of receptor tyrosine kinases and their ligands in the establishment of the vomeronasal projection in the mouse. Our data show intriguing differential expression patterns of ephrin-A5 on vomeronasal axons and of EphA6 in the accessory olfactory bulb (AOB), such that axons with high ligand concentration project onto regions of the AOB with high receptor concentration and vice versa. These data suggest a mechanism for development of this projection that is the opposite of the repellent interaction between Eph receptors and ligands observed in other systems. In support of this idea, when given the choice of whether to grow on lanes containing EphA-F(c)/laminin or F(c)/laminin protein (in the stripe assay), vomeronasal axons prefer to grow on EphA-F(c)/laminin. Analysis of ephrin-A5 mutant mice revealed a disturbance of the topographic targeting of vomeronasal axons to the AOB. In summary, these data, which are derived from in vitro and in vivo experiments, indicate an important role of the EphA family in setting up the vomeronasal projection.


2018 ◽  
Vol 53 (2) ◽  
pp. 133-138 ◽  
Author(s):  
S Khan ◽  
TA Banu ◽  
S Akter ◽  
B Goswami ◽  
M Islam ◽  
...  

An efficient in vitro regeneration system was developed for Rauvolfia serpentina L. through direct and indirect organogenesis from nodal and leaf explants. Among the different growth regulators, MS medium supplemented with 2.0 mg/l BAP, 0.5mg/l IAA and 0.02mg/l NAA found best for the multiple shoot formation from nodal segments. In this combination 98% explants produced multiple shoots and the average number of shoots per explants is 13∙4. The frequency of callus induction and multiple shoot induction from leaves was highest 88% in MS medium supplemented with 2.0 mg/l BAP, where mean number of shoots/explants was 12.5. The highest frequency of root induction (80%) and mean number of roots/plantlets (10) were obtained on half strength of MS medium containing 0.2 mg/l IBA. The rooted plantlets were transferred for hardening following acclimatization and finally were successfully established in the field.Bangladesh J. Sci. Ind. Res.53(2), 133-138, 2018


2006 ◽  
Vol 86 (1) ◽  
pp. 63-69
Author(s):  
Seedhabadee Ganeshan ◽  
Brian J Weir ◽  
Monica Båga ◽  
Brian G Rossnagel ◽  
Ravindra N Chibbar

A simple two-step model for evaluation of in vitro regeneration protocols is proposed based on callus induction and regeneration from immature scutella of two Canadian barley (Hordeum vulgare L.) genotypes, AC Metcalfe and SB92559 using the Enhanced Regeneration System (ERS). The number of explants producing embryogenic callus, the number of plants per embryogenic callus and the number of plants per explant were considered. Tissue culture parameters included three combinations of growth regulators, two carbon sources in culture media, and three cold treatment regimes of spikes prior to scutella isolation. Culture medium containing 5 µM 2,4-dichlorophenoxy acetic acid (2,4-D) and 0.5 µM benzyl adenine (BA) induced the highest percent of embryogenic calli and the highest number of shoots per embryogenic callus from AC Metcalfe. Medium containing 3.75 µM 2,4-D and 0.75 µM BA gave the best response for SB92559. Both genotypes produced more shoots on maltose than on sucrose medium. A 2-d treatment of spikes at 4°C resulted in best response for SB92559. Regeneration response from AC Metcalfe scutella from spikes was unaffected by being subjected to 2, 4 or 6 d of cold. Conditions resulting in best responses from both genotypes were tested on four commercial barley varieties. However, these lines showed inferior regeneration compared to SB92559 and AC Metcalfe. Key words: Hordeum vulgare, scutella, embryogenic callus, shoot production


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 46-46
Author(s):  
Loic Ysebaert ◽  
Mary Poupot ◽  
Yovan Sanchez-Ruiz ◽  
Camille Laurent ◽  
Guy Laurent ◽  
...  

Abstract Abstract 46 Introduction: CLL cells interact with many accessory cells in an environment mimicking that of normal mature B cells. Role of antigen, cytokines, adhesion pathways are critical for many aspects in the disease course (proliferation/survival, migration or homing, drug resistance, and presumably relapse). Nurse-like cells (NLC) belong to a monocytic-derived, bystander population among CLL lymph node and spleen stromal cells. Aim: To investigate the nature, functions, and location of NLC within CLL microenvironment. Methods: Gene expression profiles (GEP) from in vitro expanded NLC from patients (n=10) were produced and compared to those from normal CD14+ monocytes, M1-polarized macrophages, M2-polarized macrophages and tumor-associated macrophages (produced in the lab or downloaded from GEO datasets). Principal Component Analysis was used to categorize these five populations of cells and in-house-built GSEA software was used for functional interpretation of their relevant gene lists. Protein expression patterns were validated with multi-analyte ELISArray kits, proteome profiler arrays, flow cytometry (FC) or immunohistochemistry (IHC). Results: New insights into the physiopathological role of NLC in CLL are suggested from five lines of evidence: 1/a Òmonocytic gene signatureÓ (i.e. a set of 549 genes) is shared by the NLC and the monocyte subtypes. The genes over-represented in NLC vs normal monocytes pinpointed positive modulation of apoptotic cell clearance (scavenger, mannose and complement receptors, LXRalpha), lipid metabolism (Apolipoprotein E, PPAR signaling), extracellular matrix-receptor interactions (integrins, SPARC, Matrix MetalloProteinases) and actin cytoskeleton remodeling. 2/unsupervised clustering show that NLC represent an M2-skewed, TAM-like cell population. They down-regulate mRNA and proteins for classic M1 inflammatory markers (e.g. IL-1, IL-6, IL-12, COX2) while increase secretion of TGFbeta, IL-10, CCL17 and CCL22 soluble factors. 3/these and previously published observations suggest that B-CLL-to-NLC interactions may orchestrate immunosuppression in this disease. PBMCs from Òwatch and waitÓ CLL patients (all stage A/Rai 0, mutated IgVH, low risk cytogenetics profile) or healthy donors were stimulated with anti-CD3/CD28 beads + IL-2, either in standard RPMI+10% FCS or in conditioned medium (CM, after 14d CLL-NLC co-culture in vitro) and their proliferation/phenotype were compared after 2 weeks. Significant expansion of T cells with Treg (CD4+CD25+FoxP3+) phenotype was observed only from CLL PBMCs grown in conditioned medium (mean % Treg: 2.85 vs 3.05 in CM for normal PBMCs, and 1.54 vs 15.9 in CM for CLL PBMCs, P< 0.05). 4/although NLC make immune synapses with live B-CLL, they do not phagocytose them. Over-expression of CD47 (ÒdonÕt eat meÓ signal) by B-CLL cells (mfi= 3490 vs 2581 on normal cells, P< 0.05, n=18) may provide them with a protective signal against NLC. 5/from our GEP, flow cytometric and IHC analyses, we propose CD163 (classic M2 marker) as a reliable tool to identify NLC in vivo. Although in vitro, CLL cells can pervert healthy donor monocytes into NLC, only CLL-derived NLC are truly CD14+ CD163+. In vivo, CD163 staining reveals putative NLC in CLL lymph nodes(LN)/spleen sections but not in bone marrow. In LN from all patients, NLC reside in the subcapsular areas and line vessel structures, suggesting a role in CLL cells trafficking. Most interestingly, NLC infiltrate pseudofollicles structures only in a subset of cases. We will present updated IHC and clinical presentation correlation studies. Conclusions: Our results suggest that the role of NLC in CLL might be broader than initially thought. Beside of nursing and conferring drug resistance, NLC may also be crucial in the setting of immunosuppression, of CLL cells recruitment, and should thus be considered as therapeutic targets. Disclosures: Off Label Use: GA101 is not currently approved for CLL treatment.


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