scholarly journals Transcription factors MhyFIL1 and MhyFIL3 (Monotropa hypopitys) determine the asymmetric development of above-ground lateral organs in plants

2019 ◽  
Vol 23 (4) ◽  
pp. 405-411
Author(s):  
A. V. Shchennikova ◽  
A. M. Kamionskaya ◽  
A. V. Nezhdanova ◽  
K. S. Gavrilova ◽  
M. A. Filyushin ◽  
...  

It is believed that the complete mycoheterotroph pinesap Monotropa hypopitys adaptively evolved from a photosynthetic mycorrhizal ancestor, which had lost its photosynthetic apparatus and vegetative organs (stem and leaves). The aerial part of the plant is a reproductive axis with sterile bracts and inflorescence with a flower type canonical for higher plants. The origin of leaves and leaf-like lateral organs is associated, among other factors, with the evolution of the YABBY genes, which are divided into“vegetative” and evolutionarily recent“reproductive” genes, with regard to their expression profiles. The study of the vegetative YABBY genes in pinesap will determine whether their functions (identification of cell identity on the abaxial surface of the lateral organs) are preserved in the leafless plant. In this study, the structural and phylogenetic analysis of the pinesap vegetative genes MhyFIL1 and MhyFIL3 is performed, the main conserved domains and motifs of the encoded proteins are characterized, and it is confirmed that the genes belong to the vegetative clade YABBY3/FIL. The effect of heterologous ectopic expression of the MhyFIL1 and MhyFIL3 genes on the phenotype of transgenic tobacco Nicotiana tabacum is evaluated. The leaves formed by both types of plants, 35S::MhyFIL1 and 35S::MhyFIL3, were narrower than in control plants and were twisted due to the changed identity of adaxial surface cells. Also, changes in the architecture of the aerial part and the root system of transgenic plants, including aberrant phyllotaxis and arrest of the shoot and root apical meristem development, were noted. Some of the 35S::MhyFIL1 and 35S::MhyFIL3 plants died as early as the stage of the formation of the first leaves, others did not bloom, and still others had a greatly prolonged vegetation period and formed fewer flowers than normal ones. The flowers had no visible differences from the control except for fragile pedicles. Thus, the absence of structural changes from the M. hypopitys flower in comparison to autotrophic species and the effect of MhyFIL1/3 heterologous expression on the development of tobacco plants indicate the preservation of the functions of the vegetative YABBY genes by the MhyFIL1/3 genes in pinesap. Moreover, the activity of YABBY transcription factors of the FIL clade in M. hypopitys is not directly related to the loss of the ability of pinesap to form leaves during the evolutionary transition from autotrophic nutrition to heterotrophy.

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Graciela Ruiz ◽  
Heriberto A. Valencia-González ◽  
Delia Pérez-Montiel ◽  
Felipe Muñoz ◽  
Rodolfo Ocadiz-Delgado ◽  
...  

Transcription factors OCT4, SOX2, KLF4, C-MYC, and NANOG (OSKM-N) regulate pluripotency and stemness, and their ectopic expression reprograms human and murine fibroblasts that constitute the key of regenerative medicine. To determine their contribution to cell transformation, we analyzed the gene expression profiles of these transcription factors in cervical cancer samples and found that they are preferentially expressed in the tumor component. Also, cancer stem cell-enriched cultures grown as sphere cultures showed overexpression of OSKM-N genes. Importantly, we observed that lentiviral-mediated transduction of these factors confers, to a nontumorigenic immortalized human cell line, properties of cancer stem cells as the ability to form tumors in a mouse model. When we performed a meta-analysis using microarray data from cervical cancer biopsies and normal tissues, we found that the expression of OSKM-N and some target genes allowed separating tumor and normal tissues between samples, which enhanced the importance of OSKM-N in the tumorigenesis. Finally, we analyzed and compared both transcript and protein expression profiles of these factors within a cohort of patients with cervical cancer. To our knowledge, this is the first time that the expression of OSKM-N is described to induce one of the main characteristics of the cancer stem cell, the tumorigenicity. And, more importantly, its exogenous expression in a nontumorigenic cell line is sufficient to induce a tumorigenic phenotype; furthermore, the differential expression of this transcription factor distinguishes tumor tissue and normal tissue in cervical samples.


2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Anna V. Shchennikova ◽  
Marya A. Slugina ◽  
Alexey V. Beletsky ◽  
Mikhail A. Filyushin ◽  
Andrey A. Mardanov ◽  
...  

Monotropa hypopitysis a mycoheterotrophic, nonphotosynthetic plant acquiring nutrients from the roots of autotrophic trees through mycorrhizal symbiosis, and, similar to other extant plants, forming asymmetrical lateral organs during development. The members of the YABBY family of transcription factors are important players in the establishment of leaf and leaf-like organ polarity in plants. This is the first report on the identification ofYABBYgenes in a mycoheterotrophic plant devoid of aboveground vegetative organs. SevenM. hypopitys YABBYmembers were identified and classified into four clades. By structural analysis of putative encoded proteins, we confirmed the presence of YABBY-defining conserved domains and identified novel clade-specific motifs. Transcriptomic and qRT-PCR analyses of different tissues revealedMhyYABBYtranscriptional patterns, which were similar to those of orthologousYABBYgenes from other angiosperms. These data should contribute to the understanding of the role of theYABBYgenes in the regulation of developmental and physiological processes in achlorophyllous leafless plants.


Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 669
Author(s):  
Shuchi Smita ◽  
Michael Robben ◽  
Anup Deuja ◽  
Monica Accerbi ◽  
Pamela J. Green ◽  
...  

Transition of grapevine buds from paradormancy to endodormancy is coordinated by changes in gene expression, phytohormones, transcription factors, and other molecular regulators, but the mechanisms involved in transcriptional and post-transcriptional regulation of dormancy stages are not well delineated. To identify potential regulatory targets, an integrative analysis of differential gene expression profiles and their inverse relationships with miRNA abundance was performed in paradormant (long day (LD) 15 h) or endodormant (short day (SD), 13 h) Vitis riparia buds. There were 400 up- and 936 downregulated differentially expressed genes in SD relative to LD budsGene set and gene ontology enrichment analysis indicated that hormone signaling and cell cycling genes were downregulated in SD relative to LD buds. miRNA abundance and inverse expression analyses of miRNA target genes indicated increased abundance of miRNAs that negatively regulate genes involved with cell cycle and meristem development in endodormant buds and miRNAs targeting starch metabolism related genes in paradormant buds. Analysis of interactions between abundant miRNAs and transcription factors identified a network with coinciding regulation of cell cycle and epigenetic regulation related genes in SD buds. This network provides evidence for cross regulation occurring between miRNA and transcription factors both upstream and downstream of MYB3R1.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nurshafika Mohd Sakeh ◽  
Siti Nor Akmar Abdullah ◽  
Mohammad Nazri Abdul Bahari ◽  
Azzreena Mohamad Azzeme ◽  
Noor Azmi Shaharuddin ◽  
...  

Abstract Background Hemibiotrophic pathogen such as the fungal pathogen Ganoderma boninense that is destructive to oil palm, manipulates host defense mechanism by strategically switching from biotrophic to necrotrophic phase. Our previous study revealed two distinguishable expression profiles of oil palm genes that formed the basis in deducing biotrophic phase at early interaction which switched to necrotrophic phase at a later stage of infection. Results The present report is a continuing study from our previous published transcriptomic profiling of oil palm seedlings against G. boninense. We focused on identifying differentially expressed genes (DEGs) encoding transcription factors (TFs) from the same RNA-seq data; resulting in 106 upregulated and 108 downregulated TFs being identified. The DEGs are involved in four established defense-related pathways responsible for cell wall modification, reactive oxygen species (ROS)-mediated signaling, programmed cell death (PCD) and plant innate immunity. We discovered upregulation of JUNGBRUNNEN 1 (EgJUB1) during the fungal biotrophic phase while Ethylene Responsive Factor 113 (EgERF113) demonstrated prominent upregulation when the palm switches to defense against necrotrophic phase. EgJUB1 was shown to have a binding activity to a 19 bp palindromic SNBE1 element, WNNYBTNNNNNNNAMGNHW found in the promoter region of co-expressing EgHSFC-2b. Further in silico analysis of promoter regions revealed co-expression of EgJUB1 with TFs containing SNBE1 element with single nucleotide change at either the 5th or 18th position. Meanwhile, EgERF113 binds to both GCC and DRE/CRT elements promoting plasticity in upregulating the downstream defense-related genes. Both TFs were proven to be nuclear-localized based on subcellular localization experiment using onion epidermal cells. Conclusion Our findings demonstrated unprecedented transcriptional reprogramming of specific TFs potentially to enable regulation of a specific set of genes during different infection phases of this hemibiotrophic fungal pathogen. The results propose the intricacy of oil palm defense response in orchestrating EgJUB1 during biotrophic and EgERF113 during the subsequent transition to the necrotrophic phase. Binding of EgJUB1 to SNBE motif instead of NACBS while EgERF113 to GCC-box and DRE/CRT motifs is unconventional and not normally associated with pathogen infection. Identification of these phase-specific oil palm TFs is important in designing strategies to tackle or attenuate the progress of infection.


Genes ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 439
Author(s):  
Avinash Chandra Rai ◽  
Eyal Halon ◽  
Hanita Zemach ◽  
Tali Zviran ◽  
Isaac Sisai ◽  
...  

In mango (Mangifera indica L.), fruitlet abscission limits productivity. The INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) peptide acts as a key component controlling abscission events in Arabidopsis. IDA-like peptides may assume similar roles in fruit trees. In this study, we isolated two mango IDA-like encoding-genes, MiIDA1 and MiIDA2. We used mango fruitlet-bearing explants and fruitlet-bearing trees, in which fruitlets abscission was induced using ethephon. We monitored the expression profiles of the two MiIDA-like genes in control and treated fruitlet abscission zones (AZs). In both systems, qRT-PCR showed that, within 24 h, both MiIDA-like genes were induced by ethephon, and that changes in their expression profiles were associated with upregulation of different ethylene signaling-related and cell-wall modifying genes. Furthermore, ectopic expression of both genes in Arabidopsis promoted floral-organ abscission, and was accompanied by an early increase in the cytosolic pH of floral AZ cells—a phenomenon known to be linked with abscission, and by activation of cell separation in vestigial AZs. Finally, overexpression of both genes in an Atida mutant restored its abscission ability. Our results suggest roles for MiIDA1 and MiIDA2 in affecting mango fruitlet abscission. Based on our results, we propose new possible modes of action for IDA-like proteins in regulating organ abscission.


Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 364
Author(s):  
Rachel M. McCoy ◽  
Russell Julian ◽  
Shoban R. V. Kumar ◽  
Rajeev Ranjan ◽  
Kranthi Varala ◽  
...  

Upon sensing developmental or environmental cues, epigenetic regulators transform the chromatin landscape of a network of genes to modulate their expression and dictate adequate cellular and organismal responses. Knowledge of the specific biological processes and genomic loci controlled by each epigenetic regulator will greatly advance our understanding of epigenetic regulation in plants. To facilitate hypothesis generation and testing in this domain, we present EpiNet, an extensive gene regulatory network (GRN) featuring epigenetic regulators. EpiNet was enabled by (i) curated knowledge of epigenetic regulators involved in DNA methylation, histone modification, chromatin remodeling, and siRNA pathways; and (ii) a machine-learning network inference approach powered by a wealth of public transcriptome datasets. We applied GENIE3, a machine-learning network inference approach, to mine public Arabidopsis transcriptomes and construct tissue-specific GRNs with both epigenetic regulators and transcription factors as predictors. The resultant GRNs, named EpiNet, can now be intersected with individual transcriptomic studies on biological processes of interest to identify the most influential epigenetic regulators, as well as predicted gene targets of the epigenetic regulators. We demonstrate the validity of this approach using case studies of shoot and root apical meristem development.


Author(s):  
Kee-Pyo Kim ◽  
Dong Wook Han ◽  
Johnny Kim ◽  
Hans R. Schöler

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.


2004 ◽  
Vol 3 (5) ◽  
pp. 1111-1123 ◽  
Author(s):  
Susan Nicholls ◽  
Melissa Straffon ◽  
Brice Enjalbert ◽  
André Nantel ◽  
Susan Macaskill ◽  
...  

ABSTRACT In Saccharomyces cerevisiae, the (C2H2)2 zinc finger transcription factors Msn2 and Msn4 play central roles in responses to a range of stresses by activating gene transcription via the stress response element (STRE; CCCCT). The pathogen Candida albicans displays stress responses that are thought to help it survive adverse environmental conditions encountered within its human host. However, these responses differ from those in S. cerevisiae, and hence we predicted that the roles of Msn2- and Msn4-like proteins might have been functionally reassigned in C. albicans. C. albicans has two such proteins: CaMsn4 and Mnl1 (for Msn2- and Msn4-like). CaMSN4, but not MNL1, weakly complemented the inability of an S. cerevisiae msn2 msn4 mutant to activate a STRE-lacZ reporter. Also, the disruption of CaMsn4 and Mnl1 had no discernible effect upon the resistance of C. albicans to heat, osmotic, ethanol, nutrient, oxidative, or heavy-metal stress or upon the stress-activated transcriptome in C. albicans. Furthermore, although Cap1-dependent activation of a Yap response element-luciferase reporter was observed, a STRE reporter was not activated in response to stresses in C. albicans. Ectopic expression of CaMsn4 or Mnl1 did not affect the cellular or molecular responses of C. albicans to stress. Under the conditions tested, the putative activation and DNA binding domains of CaMsn4 did not appear to be functional. These data suggest that CaMsn4 and Mnl1 do not contribute significantly to stress responses in C. albicans. The data are consistent with the idea that stress signaling in this fungus has diverged significantly from that in budding yeast.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Guangzhong Xu ◽  
Kai Li ◽  
Nengwei Zhang ◽  
Bin Zhu ◽  
Guosheng Feng

Background. Construction of the transcriptional regulatory network can provide additional clues on the regulatory mechanisms and therapeutic applications in gastric cancer.Methods. Gene expression profiles of gastric cancer were downloaded from GEO database for integrated analysis. All of DEGs were analyzed by GO enrichment and KEGG pathway enrichment. Transcription factors were further identified and then a global transcriptional regulatory network was constructed.Results. By integrated analysis of the six eligible datasets (340 cases and 43 controls), a bunch of 2327 DEGs were identified, including 2100 upregulated and 227 downregulated DEGs. Functional enrichment analysis of DEGs showed that digestion was a significantly enriched GO term for biological process. Moreover, there were two important enriched KEGG pathways: cell cycle and homologous recombination. Furthermore, a total of 70 differentially expressed TFs were identified and the transcriptional regulatory network was constructed, which consisted of 566 TF-target interactions. The top ten TFs regulating most downstream target genes were BRCA1, ARID3A, EHF, SOX10, ZNF263, FOXL1, FEV, GATA3, FOXC1, and FOXD1. Most of them were involved in the carcinogenesis of gastric cancer.Conclusion. The transcriptional regulatory network can help researchers to further clarify the underlying regulatory mechanisms of gastric cancer tumorigenesis.


2010 ◽  
Vol 100 (6) ◽  
pp. 573-581 ◽  
Author(s):  
Tingquan Wu ◽  
An Guo ◽  
Yanying Zhao ◽  
Xiaomeng Wang ◽  
Ying Wang ◽  
...  

Lumazine synthase (LS) catalyzes the penultimate reaction in the multistep riboflavin biosynthesis pathway, which is involved in plant defenses. Plant defenses are often subject to synergistic effects of jasmonic acid and ethylene whereas LS is a regulator of jasmonic acid signal transduction. However, little is known about whether the enzyme contributes to defense responses. To study the role of LS in plant pathogen defenses, we generated transgenic tobacco expressing the rice (Oryza sativa) LS gene, OsLS. OsLS was cloned and found to have strong identity with its homologues in higher plants and less homology to microbial orthologues. The OsLS protein localized to chloroplasts in three OsLS-expressing transgenic tobacco (LSETT) lines characterized as enhanced in growth and defense. Compared with control plants, LSETT had higher content of both riboflavin and the cofactors flavin mononucleotide and flavin adenine dinucleotide. In LSETT, jasmonic acid and ethylene were elevated, the expression of defense-related genes was induced, levels of resistance to pathogens were enhanced, and resistance was effective to viral, bacterial, and oomycete pathogens. Extents of OsLS expression correlated with increases in flavin, jasmonic acid, and ethylene content, and correlated with increases in resistance levels, suggesting a role for OsLS in defense responses.


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