The Roles of Plant Hormones and Their Interactions with Regulatory Genes in Determining Meristem Activity

Plants, unlike animals, have developed a unique system in which they continue to form organs throughout their entire life cycle, even after embryonic development. This is possible because plants possess a small group of pluripotent stem cells in their meristems. The shoot apical meristem (SAM) plays a key role in forming all of the aerial structures of plants, including floral meristems (FMs). The FMs subsequently give rise to the floral organs containing reproductive structures. Studies in the past few decades have revealed the importance of transcription factors and secreted peptides in meristem activity using the model plant Arabidopsis thaliana. Recent advances in genomic, transcriptomic, imaging, and modeling technologies have allowed us to explore the interplay between transcription factors, secreted peptides, and plant hormones. Two different classes of plant hormones, cytokinins and auxins, and their interaction are particularly important for controlling SAM and FM development. This review focuses on the current issues surrounding the crosstalk between the hormonal and genetic regulatory network during meristem self-renewal and organogenesis.

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The CLV-WUS Stem Cell Signaling Pathway: A Roadmap to Crop Yield Optimization

Plants ◽

10.3390/plants7040087 ◽

2018 ◽

Vol 7 (4) ◽

pp. 87 ◽

Cited By ~ 18

Author(s):

Jennifer Fletcher

Keyword(s):

Stem Cell ◽

Shoot Apical Meristem ◽

Apical Meristem ◽

Higher Plants ◽

Yield Traits ◽

Yield Optimization ◽

Agricultural Plant ◽

Stem Cell Maintenance ◽

Model Plant Arabidopsis Thaliana ◽

Floral Meristems

The shoot apical meristem at the growing shoot tip acts a stem cell reservoir that provides cells to generate the entire above-ground architecture of higher plants. Many agronomic plant yield traits such as tiller number, flower number, fruit number, and kernel row number are therefore defined by the activity of the shoot apical meristem and its derivatives, the floral meristems. Studies in the model plant Arabidopsis thaliana demonstrated that a molecular negative feedback loop called the CLAVATA (CLV)-WUSCHEL (WUS) pathway regulates stem cell maintenance in shoot and floral meristems. CLV-WUS pathway components are associated with quantitative trait loci (QTL) for yield traits in crop plants such as oilseed, tomato, rice, and maize, and may have played a role in crop domestication. The conservation of these pathway components across the plant kingdom provides an opportunity to use cutting edge techniques such as genome editing to enhance yield traits in a wide variety of agricultural plant species.

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AtPiezo Plays an Important Role in Root Cap Mechanotransduction

International Journal of Molecular Sciences ◽

10.3390/ijms22010467 ◽

2021 ◽

Vol 22 (1) ◽

pp. 467

Author(s):

Xianming Fang ◽

Beibei Liu ◽

Qianshuo Shao ◽

Xuemei Huang ◽

Jia Li ◽

...

Keyword(s):

Plant Root ◽

Mechanical Force ◽

Root Cap ◽

Mechanical Stimuli ◽

The Past ◽

Physiological Processes ◽

Model Plant Arabidopsis Thaliana ◽

Mechanosensitive Ion Channel ◽

Initial Perception ◽

Plant Arabidopsis Thaliana

Plants encounter a variety of mechanical stimuli during their growth and development. It is currently believed that mechanosensitive ion channels play an essential role in the initial perception of mechanical force in plants. Over the past decade, the study of Piezo, a mechanosensitive ion channel in animals, has made significant progress. It has been proved that the perception of mechanical force in various physiological processes of animals is indispensable. However, little is still known about the function of its homologs in plants. In this study, by investigating the function of the AtPiezo gene in the model plant Arabidopsis thaliana, we found that AtPiezo plays a role in the perception of mechanical force in plant root cap and the flow of Ca2+ is involved in this process. These findings allow us to understand the function of AtPiezo from the perspective of plants and provide new insights into the mechanism of plant root cap in response to mechanical stimuli.

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Derivation of naive-type induced pluripotent stem cells in cattle using piggyBac transposition of doxycycline-inducible transcription factors

Reproduction Abstracts ◽

10.1530/repabs.1.p184 ◽

2014 ◽

Author(s):

Takamasa Kawaguchi ◽

Tomoyuki Tsukiyama ◽

Naojiro Minami ◽

Masayasu Yamada ◽

Shuichi Matsuyama ◽

...

Keyword(s):

Stem Cells ◽

Transcription Factors ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Induced Pluripotent

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RNA-Seq Provides New Insights into the Molecular Events Involved in “Ball-Skin versus Bladder Effect” on Fruit Cracking in Litchi

International Journal of Molecular Sciences ◽

10.3390/ijms22010454 ◽

2021 ◽

Vol 22 (1) ◽

pp. 454

Author(s):

Jun Wang ◽

Xiao Fang Wu ◽

Yong Tang ◽

Jian Guo Li ◽

Ming Lei Zhao

Keyword(s):

Transcription Factors ◽

Plant Hormones ◽

Fruit Development ◽

Economic Value ◽

Lipid Synthesis ◽

Expression Level ◽

Agricultural Product ◽

Rna Seq ◽

Fruit Cracking ◽

Molecular Events

Fruit cracking is a disorder of fruit development in response to internal or external cues, which causes a loss in the economic value of fruit. Therefore, exploring the mechanism underlying fruit cracking is of great significance to increase the economic yield of fruit trees. However, the molecular mechanism underlying fruit cracking is still poorly understood. Litchi, as an important tropical and subtropical fruit crop, contributes significantly to the gross agricultural product in Southeast Asia. One important agricultural concern in the litchi industry is that some famous varieties with high economic value such as ‘Nuomici’ are susceptible to fruit cracking. Here, the cracking-susceptible cultivar ‘Nuomici’ and cracking-resistant cultivar ‘Huaizhi’ were selected, and the samples including pericarp and aril during fruit development and cracking were collected for RNA-Seq analysis. Based on weighted gene co-expression network analysis (WGCNA) and the “ball-skin versus bladder effect” theory (fruit cracking occurs upon the aril expanding pressure exceeds the pericarp strength), it was found that seven co-expression modules genes (1733 candidate genes) were closely associated with fruit cracking in ‘Nuomici’. Importantly, we propose that the low expression level of genes related to plant hormones (Auxin, Gibberellins, Ethylene), transcription factors, calcium transport and signaling, and lipid synthesis might decrease the mechanical strength of pericarp in ‘Nuomici’, while high expression level of genes associated with plant hormones (Auxin and abscisic acid), transcription factors, starch/sucrose metabolism, and sugar/water transport might increase the aril expanding pressure, thereby resulting in fruit cracking in ‘Nuomici’. In conclusion, our results provide comprehensive molecular events involved in the “ball-skin versus bladder effect” on fruit cracking in litchi.

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Biological importance of OCT transcription factors in reprogramming and development

Experimental & Molecular Medicine ◽

10.1038/s12276-021-00637-4 ◽

2021 ◽

Author(s):

Kee-Pyo Kim ◽

Dong Wook Han ◽

Johnny Kim ◽

Hans R. Schöler

Keyword(s):

Stem Cells ◽

Transcription Factors ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Ectopic Expression ◽

Donor Cell ◽

Structural Components ◽

Oct4 Expression ◽

Reprogramming Factors ◽

Induced Pluripotent

AbstractEctopic expression of Oct4, Sox2, Klf4 and c-Myc can reprogram somatic cells into induced pluripotent stem cells (iPSCs). Attempts to identify genes or chemicals that can functionally replace each of these four reprogramming factors have revealed that exogenous Oct4 is not necessary for reprogramming under certain conditions or in the presence of alternative factors that can regulate endogenous Oct4 expression. For example, polycistronic expression of Sox2, Klf4 and c-Myc can elicit reprogramming by activating endogenous Oct4 expression indirectly. Experiments in which the reprogramming competence of all other Oct family members tested and also in different species have led to the decisive conclusion that Oct proteins display different reprogramming competences and species-dependent reprogramming activity despite their profound sequence conservation. We discuss the roles of the structural components of Oct proteins in reprogramming and how donor cell epigenomes endow Oct proteins with different reprogramming competences.

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Development of Multilayer Mesenchymal Stem Cell Cell Sheets

International Journal of Translational Medicine ◽

10.3390/ijtm1010002 ◽

2021 ◽

Vol 1 (1) ◽

pp. 4-24

Author(s):

Jun Ochiai ◽

Yutaka Niihara ◽

Joan Oliva

Keyword(s):

Stem Cells ◽

Stromal Cells ◽

Pluripotent Stem Cells ◽

Cell Sheets ◽

Gene Therapies ◽

The Past ◽

Long Term Effect ◽

Induced Pluripotent ◽

New Guidelines

Cell and gene therapies have been developing dramatically over the past decade. To face and adapt to the development of these new therapies, the Food and Drug Administration (FDA) wrote and updated new guidelines from 2016 and keep updating them. Mesenchymal stem cells (MSCs) are the most used cells for treatment, far ahead from the induced pluripotent stem cells (iPSCs), based on registered clinical trials at clinicaltrials.gov. They are widely used because of their differentiation capacity and their anti-inflammatory properties, but some controversies still require clear answers. Additional studies are needed to determine the dosage, the number, and the route of injections (location and transplantation method), and if allogenic MSCs are safe compared to autologous MSC injection, including their long-term effect. In this review, we summarize the research our company is conducting with the adipose stromal cells in engineering cell sheets and their potential application.

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