A passion fruit putative ortholog of the SOMATIC EMBRYOGENESIS RECEPTOR KINASE1 gene is expressed throughout the in vitro de novo shoot organogenesis developmental program

Plant regeneration is essential for survival upon wounding and is, hence, considered to be a strong natural selective trait. The capacity of plant tissues to regenerate in vitro, however, varies substantially between and within species and depends on the applied incubation conditions. Insight into the genetic factors underlying this variation may help to improve numerous biotechnological applications that exploit in vitro regeneration. Here, we review the state of the art on the molecular framework of de novo shoot organogenesis from root explants in Arabidopsis, which is a complex process controlled by multiple quantitative trait loci of various effect sizes. Two types of factors are distinguished that contribute to natural regenerative variation: master regulators that are conserved in all experimental systems (e.g., WUSCHEL and related homeobox genes) and conditional regulators whose relative role depends on the explant and the incubation settings. We further elaborate on epigenetic variation and protocol variables that likely contribute to differential explant responsivity within species and conclude that in vitro shoot organogenesis occurs at the intersection between (epi) genetics, endogenous hormone levels, and environmental influences.

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Integrating the Roles for Cytokinin and Auxin in De Novo Shoot Organogenesis: From Hormone Uptake to Signaling Outputs

International Journal of Molecular Sciences ◽

10.3390/ijms22168554 ◽

2021 ◽

Vol 22 (16) ◽

pp. 8554

Author(s):

Martin Raspor ◽

Václav Motyka ◽

Abdul Rasheed Kaleri ◽

Slavica Ninković ◽

Ljiljana Tubić ◽

...

Keyword(s):

Shoot Regeneration ◽

De Novo ◽

Shoot Organogenesis ◽

In Vitro Regeneration ◽

Genetic Regulation ◽

Auxin Signaling ◽

Plant Tissues ◽

Cultivated Plant ◽

The Media

De novo shoot organogenesis (DNSO) is a procedure commonly used for the in vitro regeneration of shoots from a variety of plant tissues. Shoot regeneration occurs on nutrient media supplemented with the plant hormones cytokinin (CK) and auxin, which play essential roles in this process, and genes involved in their signaling cascades act as master regulators of the different phases of shoot regeneration. In the last 20 years, the genetic regulation of DNSO has been characterized in detail. However, as of today, the CK and auxin signaling events associated with shoot regeneration are often interpreted as a consequence of these hormones simply being present in the regeneration media, whereas the roles for their prior uptake and transport into the cultivated plant tissues are generally overlooked. Additionally, sucrose, commonly added to the regeneration media as a carbon source, plays a signaling role and has been recently shown to interact with CK and auxin and to affect the efficiency of shoot regeneration. In this review, we provide an integrative interpretation of the roles for CK and auxin in the process of DNSO, adding emphasis on their uptake from the regeneration media and their interaction with sucrose present in the media to their complex signaling outputs that mediate shoot regeneration.

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From endosperm to triploid plants: a stepwise characterization of the de novo shoot organogenesis and morpho-agronomic aspects of an ornamental passion fruit (Passiflora foetida L.)

Plant Cell Tissue and Organ Culture (PCTOC) ◽

10.1007/s11240-021-02120-4 ◽

2021 ◽

Author(s):

Andréia Izabel Mikovski ◽

Nayara Tayane da Silva ◽

Lázara Aline Simões Silva ◽

Mariana Machado ◽

Lília Cristina de Souza Barbosa ◽

...

Keyword(s):

De Novo ◽

Shoot Organogenesis ◽

Passion Fruit ◽

Passiflora Foetida

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Cytokinin Signaling and De Novo Shoot Organogenesis

Genes ◽

10.3390/genes12020265 ◽

2021 ◽

Vol 12 (2) ◽

pp. 265

Author(s):

Katarzyna Hnatuszko-Konka ◽

Aneta Gerszberg ◽

Izabela Weremczuk-Jeżyna ◽

Izabela Grzegorczyk-Karolak

Keyword(s):

Cell Fate ◽

Molecular Interactions ◽

De Novo ◽

Shoot Organogenesis ◽

Control Mechanisms ◽

Cytokinin Signaling ◽

Tissue Sections ◽

Transcriptional Reprogramming ◽

Genetic Events

The ability to restore or replace injured tissues can be undoubtedly named among the most spectacular achievements of plant organisms. One of such regeneration pathways is organogenesis, the formation of individual organs from nonmeristematic tissue sections. The process can be triggered in vitro by incubation on medium supplemented with phytohormones. Cytokinins are a class of phytohormones demonstrating pleiotropic effects and a powerful network of molecular interactions. The present study reviews existing knowledge on the possible sequence of molecular and genetic events behind de novo shoot organogenesis initiated by cytokinins. Overall, the review aims to collect reactions encompassed by cytokinin primary responses, starting from phytohormone perception by the dedicated receptors, to transcriptional reprogramming of cell fate by the last module of multistep-phosphorelays. It also includes a brief reminder of other control mechanisms, such as epigenetic reprogramming.

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(405) Regeneration of Venus Fly Trap (Dionaea muscipula Ellis) from Leaf Culture

HortScience ◽

10.21273/hortsci.40.4.1062f ◽

2005 ◽

Vol 40 (4) ◽

pp. 1062F-1063

Author(s):

Khalid M. Ahmad ◽

Syed M. A. Zobayed ◽

Praveen K. Saxena ◽

David M. Hunter

Keyword(s):

Somatic Embryogenesis ◽

Shoot Organogenesis ◽

In Vitro Regeneration ◽

Leaf Disc ◽

Leaf Explants ◽

Carnivorous Plant ◽

In Vitro Techniques ◽

Direct Shoot Organogenesis ◽

Direct Shoot

Dionaeamuscipula Ellis commonly known as Venus fly trap is an important carnivorous plant with medicinal importance. It contains certain secondary metabolites like naphthoquinones and is used in anti-aid and anti-cancer drugs and other medicines like Cornivora. Increasing interest and use as an ornamental and medicinal plant, and dietary supplement have put it in an endangered state. Development of in vitro techniques for the preservation of germplasm that is on the brink of extinction is highly demanded. A regeneration protocol for the multiplication and micropropagation of Dionaeamuscipla Ellis was established. In vitro regeneration potential of leaf explants in different concentrations and combinations of plant growth substances was investigated in this study. Seeds were grown and leaf disc explants were excised and cultured under aseptic conditions on nutritional medium containing half strength Murashige and Skoog (MS) mix with combinations of 1.0–20.0 μm BA, 2.5.0 μm IBA, 1.0–10.0 μm 2iP and 0.1–0.5μm TDZ. The cultures were kept in growth cabinet with cool white light (40–60 μmol·m-2·s-1) under 16-h photoperiod. Regeneration was recorded after 60 days with the intervals of 15 days based on the degree of shoot organogenesis and somatic embryogenesis. 1/2 MS + 0.1 TDZ appeared to be efficient for somatic embryogenesis and simple MS for direct shoot organogenesis. 1/2 MS combined with 2iP appeared to be efficient for regeneration either by direct shoot organogenesis or by somatic embryogenesis. Plants were rooted well in Cape Cundew medium. These investigations will aid in the development of a model system for clonal mass propagation and in vitro regeneration of Dionaeamuscipla Ellis.

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