Genetically Modified Plant (GMO) Using Hormone and T-DNA Technology: Regulated Gene Expression

Author(s):  
ABM Sharif Hossain ◽  
1993 ◽  
Vol 342 (1301) ◽  
pp. 241-250 ◽  

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.


2000 ◽  
Vol 14 (3) ◽  
pp. 235-239 ◽  
Author(s):  
Kevan M. A. Gartland ◽  
Angela T. McHugh ◽  
Stanislav Vitha ◽  
Karel Benes ◽  
Richard J. Irvine ◽  
...  

2006 ◽  
Vol 73 ◽  
pp. 85-96 ◽  
Author(s):  
Richard J. Reece ◽  
Laila Beynon ◽  
Stacey Holden ◽  
Amanda D. Hughes ◽  
Karine Rébora ◽  
...  

The recognition of changes in environmental conditions, and the ability to adapt to these changes, is essential for the viability of cells. There are numerous well characterized systems by which the presence or absence of an individual metabolite may be recognized by a cell. However, the recognition of a metabolite is just one step in a process that often results in changes in the expression of whole sets of genes required to respond to that metabolite. In higher eukaryotes, the signalling pathway between metabolite recognition and transcriptional control can be complex. Recent evidence from the relatively simple eukaryote yeast suggests that complex signalling pathways may be circumvented through the direct interaction between individual metabolites and regulators of RNA polymerase II-mediated transcription. Biochemical and structural analyses are beginning to unravel these elegant genetic control elements.


2020 ◽  
Author(s):  
Robert Calin-Jageman ◽  
Irina Calin-Jageman ◽  
Tania Rosiles ◽  
Melissa Nguyen ◽  
Annette Garcia ◽  
...  

[[This is a Stage 1 Registered Report manuscript. The project was submitted for review to eNeuro. Upon revision and acceptance, this version of the manuscript was pre-registered on the OSF (9/11/2019, https://osf.io/fqh8j) (but due to an oversight not posted as a preprint until July 2020). A Stage 2 manuscript is now posted as a pre-print (https://psyarxiv.com/h59jv) and is under review at eNeuro. A link to the final Stage 2 manuscript will be added when available.]]There is fundamental debate about the nature of forgetting: some have argued that it represents the decay of the memory trace, others that the memory trace persists but becomes inaccessible due to retrieval failure. These different accounts of forgetting make different predictions about savings memory, the rapid re-learning of seemingly forgotten information. If forgetting is due to decay then savings requires re-encoding and should thus involve the same mechanisms as initial learning. If forgetting is due to retrieval-failure then savings should be mechanistically distinct from encoding. In this registered report we conducted a pre-registered and rigorous test between these accounts of forgetting. Specifically, we used microarray to characterize the transcriptional correlates of a new memory (1 day from training), a forgotten memory (8 days from training), and a savings memory (8 days from training but with a reminder on day 7 to evoke a long-term savings memory) for sensitization in Aplysia californica (n = 8 samples/group). We find that the transcriptional correlates of savings are [highly similar / somewhat similar / unique] relative to new (1-day-old) memories. Specifically, savings memory and a new memory share [X] of [Y] regulated transcripts, show [strong / moderate / weak] similarity in sets of regulated transcripts, and show [r] correlation in regulated gene expression, which is [substantially / somewhat / not at all] stronger than at forgetting. Overall, our results suggest that forgetting represents [decay / retrieval-failure / mixed mechanisms].


Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1335
Author(s):  
Marina Mostafizar ◽  
Claudia Cortes-Pérez ◽  
Wanda Snow ◽  
Jelena Djordjevic ◽  
Aida Adlimoghaddam ◽  
...  

The transcription factor nuclear factor kappa B (NF-κB) is highly expressed in almost all types of cells. NF-κB is involved in many complex biological processes, in particular in immunity. The activation of the NF-κB signaling pathways is also associated with cancer, diabetes, neurological disorders and even memory. Hence, NF-κB is a central factor for understanding not only fundamental biological presence but also pathogenesis, and has been the subject of intense study in these contexts. Under healthy physiological conditions, the NF-κB pathway promotes synapse growth and synaptic plasticity in neurons, while in glia, NF-κB signaling can promote pro-inflammatory responses to injury. In addition, NF-κB promotes the maintenance and maturation of B cells regulating gene expression in a majority of diverse signaling pathways. Given this, the protein plays a predominant role in activating the mammalian immune system, where NF-κB-regulated gene expression targets processes of inflammation and host defense. Thus, an understanding of the methodological issues around its detection for localization, quantification, and mechanistic insights should have a broad interest across the molecular neuroscience community. In this review, we summarize the available methods for the proper detection and analysis of NF-κB among various brain tissues, cell types, and subcellular compartments, using both qualitative and quantitative methods. We also summarize the flexibility and performance of these experimental methods for the detection of the protein, accurate quantification in different samples, and the experimental challenges in this regard, as well as suggestions to overcome common challenges.


Sign in / Sign up

Export Citation Format

Share Document