scholarly journals Molecular Analysis of Carotenoid Biosynthesis in Plants: Characterizing the Genes Psy, Pds and CrtL-e

1993 ◽  
Author(s):  
Joseph Hirschberg ◽  
Gloria A. Moore
Keyword(s):  
Gene Expression ◽  
Carotenoid Biosynthesis ◽  
Phytoene Synthase ◽  
Future Application ◽  
Carotenoid Pigment ◽  
Major Mechanism ◽  
Lycopene Cyclase ◽  
Genes Encoding ◽  
Pigment Biosynthesis ◽  
Pigment Accumulation

In this research we have studied the molecular biology of carotenoid biosynthesis in tomato. The investigations focused on the genes Pds and Psy, encoding desaturase and phytoene synthase, respectively, which are key enzymes in the biosynthetic pathway of lycopene and b-carotene. In addition, we have investigated the genes for lycopene cyclase. We have cloned from tomato and characterized the cDNA of CrtL-e, which encodes the lycopene e-cyclase, and analyzed its expression during fruit development. The results establish a paradigm for the regulation of carotenoid pigment biosynthesis during the ripening process of fruits. It is concluded that transcriptional regulation of genes that encode carotenoid-biosynthesis enzymes is the major mechanism that governs specific pigment accumulation. During the ripening of tomato fruits transcription of the genes encoding the enzymes phytoene synthase and phytoene desaturase is up-regulated, while the transcription of the genes for both lycopene cyclases decreases and thus the conversion of lycopene to subsequent carotenoids is inhibited. These findings support the working hypothesis of the molecular approach to manipulating carotenogenesis by altering gene expression in transgenic plants, and offer obvious strategies to future application in agriculture. The molecular and physiological knowledge on carotenogenesis gained in this project, suggest a concept for manipulating gene expression that will alter carotenoid composition in fruits and flowers.

scholarly journals The Role of Specific Viral Genes and Gene Products in Potyviral Pathogenicity, Host Range and Aphid Transmission

1992 ◽  
Author(s):  
John Shaw ◽  
Arieh Rosner ◽  
Thomas Pirone ◽  
Benjamin Raccah ◽  
Yehezkiel Antignus
Keyword(s):  
Gene Expression ◽  
Carotenoid Biosynthesis ◽  
Aphid Transmission ◽  
Phytoene Synthase ◽  
Future Application ◽  
Carotenoid Pigment ◽  
Major Mechanism ◽  
Lycopene Cyclase ◽  
Genes Encoding ◽  
Pigment Biosynthesis

In this research we have studied the molecular biology of carotenoid biosynthesis in tomato. The investigations focused on the genes Pds and Psy, encoding desaturase and phytoene synthase, respectively, which are key enzymes in the biosynthetic pathway of lycopene and b-carotene. In addition, we have investigated the genes for lycopene cyclase. We have cloned from tomato and characterized the cDNA of CrtL-e, which encodes the lycopene e-cyclase, and analyzed its expression during fruit development. The results establish a paradigm for the regulation of carotenoid pigment biosynthesis during the ripening process of fruits. It is concluded that transcriptional regulation of genes that encode carotenoid-biosynthesis enzymes is the major mechanism that governs specific pigment accumulation. During the ripening of tomato fruits transcription of the genes encoding the enzymes phytoene synthase and phytoene desaturase is up-regulated, while the transcription of the genes for both lycopene cyclases decreases and thus the conversion of lycopene to subsequent carotenoids is inhibited. These findings support the working hypothesis of the molecular approach to manipulating carotenogenesis by altering gene expression in transgenic plants, and offer obvious strategies to future application in agriculture. The molecular and physiological knowledge on carotenogenesis gained in this project, suggest a concept for manipulating gene expression that will alter carotenoid composition in fruits and flowers.

Control of ripening

1993 ◽  
Vol 342 (1301) ◽  
pp. 241-250 ◽  
Keyword(s):  
Gene Expression ◽  
Genetically Modified ◽  
Carotenoid Biosynthesis ◽  
New Genes ◽  
New Business ◽  
Genes Encoding ◽  
The Usa ◽  
Tomato Processing ◽  
Cell Wall Texture ◽  
Regulated Gene Expression

Ripening of fleshy fruits involves major changes in physiology and biochemistry that alter their colour, flavour, texture, aroma and nutritional value. These changes affect all cell compartments and require the expression of new genes encoding enzymes that catalyse reactions essential for the development of quality attributes. In climacteric fruits, such as tomato, ethylene functions as a hormone to stimulate changes in gene expression required for ripening. Molecular cloning experiments have led to the isolation of cDNAs encoding many ripening proteins. This has enabled the identification and manipulation of novel plant genes encoding enzymes involved in cell wall texture change, carotenoid biosynthesis, ethylene synthesis and the identification of gene control regions involved in fruit-specific, ripening-specific, and ethylene-regulated gene expression. Antisense and partial sense gene techniques have been developed to generate genetically modified plant lines in which specific genes have been permanently inactivated. These fundamental studies have led to production and evaluation of genetically modified tomato lines with improved colour, texture, storage life, and processing characteristics. Zeneca Seeds has established a new business division, the aim of which is to utilize these techniques for the development of improved fruit and vegetable varieties. In collaboration with Petoseed, Zeneca Seeds is in the process of transferring the genes leading to quality im provement of tomatoes to Petoseed’s elite tomato germplasm. The primary focus is on the development of improved processing hybrids. These are being evaluated in collaboration with Hunt Wesson, a large and diversified tomato processing company. It is planned that products based on this research will be introduced in the USA in 1995.

scholarly journals Light Harvesting-like Protein 3 Interacts with Phytoene Synthase and Is Necessary for Carotenoid and Chlorophyll Biosynthesis in Rice

Rice ◽  
2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Feng Yang ◽  
Das Debatosh ◽  
Tao Song ◽  
Jian-hua Zhang
Keyword(s):  
Light Harvesting ◽  
Genetic Manipulation ◽  
Chlorophyll Biosynthesis ◽  
Flower Color ◽  
Carotenoid Biosynthesis ◽  
Phytoene Synthase ◽  
Low Fertility ◽  
Cell Wall Modification ◽  
Light Harvesting Complex ◽  
Pigment Biosynthesis

Abstract Background Carotenoid biosynthesis is essential for the generation of photosynthetic pigments, phytohormone production, and flower color development. The light harvesting like 3 (LIL3) protein, which belongs to the light-harvesting complex protein family in photosystems, interacts with geranylgeranyl reductase (GGR) and protochlorophyllide oxidoreductase (POR) both of which are known to regulate terpenoid and chlorophyll biosynthesis, respectively, in both rice and Arabidopsis. Results In our study, a CRISPR-Cas9 generated 4-bp deletion mutant oslil3 showed aberrant chloroplast development, growth defects, low fertility rates and reduced pigment contents. A comparative transcriptomic analysis of oslil3 suggested that differentially expressed genes (DEGs) involved in photosynthesis, cell wall modification, primary and secondary metabolism are differentially regulated in the mutant. Protein-protein interaction assays indicated that LIL3 interacts with phytoene synthase (PSY) and in addition the gene expression of PSY genes are regulated by LIL3. Subcellular localization of LIL3 and PSY suggested that both are thylakoid membrane anchored proteins in the chloroplast. We suggest that LIL3 directly interacts with PSY to regulate carotenoid biosynthesis. Conclusion This study reveals a new role of LIL3 in regulating pigment biosynthesis through interaction with the rate limiting enzyme PSY in carotenoid biosynthesis in rice presenting it as a putative target for genetic manipulation of pigment biosynthesis pathways in crop plants.

scholarly journals Effect of an Introduced Phytoene Synthase Gene Expression on Carotenoid Biosynthesis in the Marine Diatom Phaeodactylum tricornutum

Marine Drugs ◽  
2015 ◽  
Vol 13 (8) ◽  
pp. 5334-5357 ◽  
Author(s):  
Takashi Kadono ◽  
Nozomu Kira ◽  
Kengo Suzuki ◽  
Osamu Iwata ◽  
Takeshi Ohama ◽  
...  
Keyword(s):  
Gene Expression ◽  
Phaeodactylum Tricornutum ◽  
Carotenoid Biosynthesis ◽  
Phytoene Synthase ◽  
Marine Diatom ◽  
Phytoene Synthase Gene

scholarly journals Carotenoid Biosynthesis in the Primitive Red Alga Cyanidioschyzon merolae

2006 ◽  
Vol 6 (3) ◽  
pp. 533-545 ◽  
Author(s):  
Francis X. Cunningham ◽  
Hansel Lee ◽  
Elisabeth Gantt
Keyword(s):  
Carotenoid Biosynthesis ◽  
Red Alga ◽  
Land Plants ◽  
Carotenoid Content ◽  
Cyanidioschyzon Merolae ◽  
Origin And Evolution ◽  
Lycopene Cyclase ◽  
Genes Encoding ◽  
Photosynthetic Organism ◽  
Β Carotene

ABSTRACT Cyanidioschyzon merolae is considered to be one of the most primitive of eukaryotic photosynthetic organisms. To obtain insights into the origin and evolution of the pathway of carotenoid biosynthesis in eukaryotic plants, the carotenoid content of C. merolae was ascertained, genes encoding enzymes of carotenoid biosynthesis in this unicellular red alga were identified, and the activities of two candidate pathway enzymes of particular interest, lycopene cyclase and β-carotene hydroxylase, were examined. C. merolae contains perhaps the simplest assortment of chlorophylls and carotenoids found in any eukaryotic photosynthetic organism: chlorophyll a, β-carotene, and zeaxanthin. Carotenoids with ε-rings (e.g., lutein), found in many other red algae and in green algae and land plants, were not detected, and the lycopene cyclase of C. merolae quite specifically produced only β-ringed carotenoids when provided with lycopene as the substrate in Escherichia coli. Lycopene β-ring cyclases from several bacteria, cyanobacteria, and land plants also proved to be high-fidelity enzymes, whereas the structurally related ε-ring cyclases from several plant species were found to be less specific, yielding products with β-rings as well as ε-rings. C. merolae lacks orthologs of genes that encode the two types of β-carotene hydroxylase found in land plants, one a nonheme diiron oxygenase and the other a cytochrome P450. A C. merolae chloroplast gene specifies a polypeptide similar to members of a third class of β-carotene hydroxylases, common in cyanobacteria, but this gene did not produce an active enzyme when expressed in E. coli. The identity of the C. merolae β-carotene hydroxylase therefore remains uncertain.

scholarly journals Mapping chromatin accessibility and active regulatory elements reveals pathological mechanisms in human gliomas

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Karolina Stępniak ◽  
Magdalena A. Machnicka ◽  
Jakub Mieczkowski ◽  
Anna Macioszek ◽  
Bartosz Wojtaś ◽  
...  
Keyword(s):  
Gene Expression ◽  
Chromatin Structure ◽  
Molecular Mechanisms ◽  
Genome Mapping ◽  
Malignant Gliomas ◽  
Regulatory Elements ◽  
Chromatin Accessibility ◽  
Multiple Tumor ◽  
Genes Encoding ◽  
Methylation Patterns

AbstractChromatin structure and accessibility, and combinatorial binding of transcription factors to regulatory elements in genomic DNA control transcription. Genetic variations in genes encoding histones, epigenetics-related enzymes or modifiers affect chromatin structure/dynamics and result in alterations in gene expression contributing to cancer development or progression. Gliomas are brain tumors frequently associated with epigenetics-related gene deregulation. We perform whole-genome mapping of chromatin accessibility, histone modifications, DNA methylation patterns and transcriptome analysis simultaneously in multiple tumor samples to unravel epigenetic dysfunctions driving gliomagenesis. Based on the results of the integrative analysis of the acquired profiles, we create an atlas of active enhancers and promoters in benign and malignant gliomas. We explore these elements and intersect with Hi-C data to uncover molecular mechanisms instructing gene expression in gliomas.

scholarly journals Alterations of mesenchymal stromal cells in cerebrospinal fluid: insights from transcriptomics and an ALS clinical trial

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ashley A. Krull ◽  
Deborah O. Setter ◽  
Tania F. Gendron ◽  
Sybil C. L. Hrstka ◽  
Michael J. Polzin ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cerebrospinal Fluid ◽  
Growth Factors ◽  
Mesenchymal Stromal Cells ◽  
Stromal Cells ◽  
Large Scale ◽  
Therapeutic Benefit ◽  
Protein Levels ◽  
Genes Encoding ◽  
Intrathecal Space

Abstract Background Mesenchymal stromal cells (MSCs) have been studied with increasing intensity as clinicians and researchers strive to understand the ability of MSCs to modulate disease progression and promote tissue regeneration. As MSCs are used for diverse applications, it is important to appreciate how specific physiological environments may stimulate changes that alter the phenotype of the cells. One need for neuroregenerative applications is to characterize the spectrum of MSC responses to the cerebrospinal fluid (CSF) environment after their injection into the intrathecal space. Mechanistic understanding of cellular biology in response to the CSF environment may predict the ability of MSCs to promote injury repair or provide neuroprotection in neurodegenerative diseases. Methods In this study, we characterized changes in morphology, metabolism, and gene expression occurring in human adipose-derived MSCs cultured in human (hCSF) or artificial CSF (aCSF) as well as examined relevant protein levels in the CSF of subjects treated with MSCs for amyotrophic lateral sclerosis (ALS). Results Our results demonstrated that, under intrathecal-like conditions, MSCs retained their morphology, though they became quiescent. Large-scale transcriptomic analysis of MSCs revealed a distinct gene expression profile for cells cultured in aCSF. The aCSF culture environment induced expression of genes related to angiogenesis and immunomodulation. In addition, MSCs in aCSF expressed genes encoding nutritional growth factors to expression levels at or above those of control cells. Furthermore, we observed a dose-dependent increase in growth factors and immunomodulatory cytokines in CSF from subjects with ALS treated intrathecally with autologous MSCs. Conclusions Overall, our results suggest that MSCs injected into the intrathecal space in ongoing clinical trials remain viable and may provide a therapeutic benefit to patients.

The oxen Gene of Drosophila Encodes a Homolog of Subunit 9 of Yeast Ubiquinol-Cytochrome c Oxidoreductase Complex: Evidence for Modulation of Gene Expression in Response to Mitochondrial Activity

Genetics ◽  
2000 ◽  
Vol 156 (4) ◽  
pp. 1727-1736 ◽  
Author(s):  
Maxim V Frolov ◽  
Elizaveta V Benevolenskaya ◽  
James A Birchler
Keyword(s):  
Gene Expression ◽  
Cytochrome C ◽  
Cellular Response ◽  
Insertion Site ◽  
Nuclear Gene ◽  
Mutant Phenotype ◽  
P Element ◽  
Mitochondrial Activity ◽  
Genes Encoding ◽  
Subunit 9

Abstract A P-element insertion in the oxen gene, ox1, has been isolated in a search for modifiers of white gene expression. The mutation preferentially exerts a negative dosage effect upon the expression of three genes encoding ABC transporters involved in pigment precursor transport, white, brown, and scarlet. A precise excision of the P element reverts the mutant phenotype. Five different transcription units were identified around the insertion site. To distinguish a transcript responsible for the mutant phenotype, a set of deletions within the oxen region was generated. Analysis of gene expression within the oxen region in the case of deletions as well as generation of transgenic flies allowed us to identify the transcript responsible for oxen function. It encodes a 6.6-kD homolog of mitochondrial ubiquinol cytochrome c oxidoreductase (QCR9), subunit 9 of the bc1 complex in yeast. In addition to white, brown, and scarlet, oxen regulates the expression of three of seven tested genes. Thus, our data provide additional evidence for a cellular response to changes in mitochondrial function. The oxen mutation provides a model for the genetic analysis in multicellular organisms of the effect of mitochondrial activity on nuclear gene expression.

scholarly journals Histone modifications form a cell-type-specific chromosomal bar code that persists through the cell cycle

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
John A. Halsall ◽  
Simon Andrews ◽  
Felix Krueger ◽  
Charlotte E. Rutledge ◽  
Gabriella Ficz ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Histone Modifications ◽  
Expression Patterns ◽  
Cell Types ◽  
Cell Type ◽  
Bar Code ◽  
Genes Encoding ◽  
Cell Type Specific ◽  
Rolling Windows

AbstractChromatin configuration influences gene expression in eukaryotes at multiple levels, from individual nucleosomes to chromatin domains several Mb long. Post-translational modifications (PTM) of core histones seem to be involved in chromatin structural transitions, but how remains unclear. To explore this, we used ChIP-seq and two cell types, HeLa and lymphoblastoid (LCL), to define how changes in chromatin packaging through the cell cycle influence the distributions of three transcription-associated histone modifications, H3K9ac, H3K4me3 and H3K27me3. We show that chromosome regions (bands) of 10–50 Mb, detectable by immunofluorescence microscopy of metaphase (M) chromosomes, are also present in G1 and G2. They comprise 1–5 Mb sub-bands that differ between HeLa and LCL but remain consistent through the cell cycle. The same sub-bands are defined by H3K9ac and H3K4me3, while H3K27me3 spreads more widely. We found little change between cell cycle phases, whether compared by 5 Kb rolling windows or when analysis was restricted to functional elements such as transcription start sites and topologically associating domains. Only a small number of genes showed cell-cycle related changes: at genes encoding proteins involved in mitosis, H3K9 became highly acetylated in G2M, possibly because of ongoing transcription. In conclusion, modified histone isoforms H3K9ac, H3K4me3 and H3K27me3 exhibit a characteristic genomic distribution at resolutions of 1 Mb and below that differs between HeLa and lymphoblastoid cells but remains remarkably consistent through the cell cycle. We suggest that this cell-type-specific chromosomal bar-code is part of a homeostatic mechanism by which cells retain their characteristic gene expression patterns, and hence their identity, through multiple mitoses.

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