This document discusses marker-free transgenics, which aim to generate transgenic plants without selectable marker genes. It describes various strategies to produce marker-free plants, including using screenable markers, co-transformation, site-specific recombination, multi-autotransformation vectors, intrachromosomal recombination, and transposon-based methods. The document concludes that developing marker-free transgenic crops could help advance crop improvement efforts and increase public acceptance of transgenic technologies.
Presented by- MD JAKIR HOSSAIN
Doctoral Research Scholar
Department of Agricultural Genetic Engineering ,
Faculty of Agricultural Sciences and Technologies,
Nigde Omer Halisdemir University, Turkey
E. Mail- mjakirbotru@gmail.com
Agrobacterium mediated gene transfer in plants.ICHHA PURAK
This power point presentation consist of 41 slides. Attempts have been made to illustrate how Agrobacterium behaves us natural genetic engineer. How it can infect a plant through wound and a part of DNA present on Ti plasmid is Tranferred and causes disease as crown gall in the infected plant. In second part of the presentation attempts have been made to describe how Agrobacterium can be utilized for iinsertion of desired gene into the plant,what manipulation are to be made with Agrobacterium.How infection and transfer of desired gene can be made possible.What is the role of plant tissue culture etc.
Somaclonal Variation in Plant tissue culture - Variation in somaclones (somatic cells of plants)
Somaclonal variation # Basis of somaclonal variation # General feature of Somaclonal variations # Types and causes of somaclonal variation # Isolation procedure of somaclones via without in-vitro method and with in-vitro method with their limitations and advantages # Detection of isolated somaclonal variation # Application (with examples respectively related to crop improvement) # Advantages and disadvantages of somaclonal variations.
https://www.youtube.com/watch?v=IZwrkgADM3I
Also watch, Gametoclonal variation slides to understand, how to changes occur in gametoclones of plants.
https://www.slideshare.net/SharmasClasses/gametoclonal-variation
Presented by- MD JAKIR HOSSAIN
Doctoral Research Scholar
Department of Agricultural Genetic Engineering ,
Faculty of Agricultural Sciences and Technologies,
Nigde Omer Halisdemir University, Turkey
E. Mail- mjakirbotru@gmail.com
Agrobacterium mediated gene transfer in plants.ICHHA PURAK
This power point presentation consist of 41 slides. Attempts have been made to illustrate how Agrobacterium behaves us natural genetic engineer. How it can infect a plant through wound and a part of DNA present on Ti plasmid is Tranferred and causes disease as crown gall in the infected plant. In second part of the presentation attempts have been made to describe how Agrobacterium can be utilized for iinsertion of desired gene into the plant,what manipulation are to be made with Agrobacterium.How infection and transfer of desired gene can be made possible.What is the role of plant tissue culture etc.
Somaclonal Variation in Plant tissue culture - Variation in somaclones (somatic cells of plants)
Somaclonal variation # Basis of somaclonal variation # General feature of Somaclonal variations # Types and causes of somaclonal variation # Isolation procedure of somaclones via without in-vitro method and with in-vitro method with their limitations and advantages # Detection of isolated somaclonal variation # Application (with examples respectively related to crop improvement) # Advantages and disadvantages of somaclonal variations.
https://www.youtube.com/watch?v=IZwrkgADM3I
Also watch, Gametoclonal variation slides to understand, how to changes occur in gametoclones of plants.
https://www.slideshare.net/SharmasClasses/gametoclonal-variation
HYBRIDIZATION & HAPLOID PRODUCTION
Introduction
WIDE HYBRIDIZATION
INTER-SPECIFIC HYBRIDIZATION
Barriers to distant hybridization
Techniques to overcome barriers
Haploids and Doubled Haploids in Plant
Production of haploids and doubled haploids
a) Induction of maternal haploids
Wide hybridization
3. In vitro induction of maternal haploids – gynogenesis
Induction of paternal haploids – Androgenesis
Production of Homozygous Diploid Plants
Application of Haploids in Plant Breeding
Importance and Implications of Anther and Pollen Culture
The isolation, culture and fusion of protoplasts is a fascinating field in plant research. Protoplast isolation and their cultures provide millions of single cells (comparable to microbial cells) for a variety of studies.
Genetic manipulation of plant and animal cells have to be confirmed for further application. One such confirmatory method is the use of stains/dyes which produces fluorescence when the recombination is successful.
A process where an embryo is derived from a single somatic cell or group of somatic cells. Somatic embryos (SEs) are formed from plant cells that are not normally involved in embryo formation.
Embryos formed by somatic embryogenesis are called Embryoids.
The process was discovered for the first time in Daucas carota L. (carrot) by Steward (1958), Reinert (1959).
What are an expression vector? Detailed description of plant gene structure. Plant expression vector systems are generally consists of Ri and Ti plasmids.
The other vectors which are generally used are DNA and RNA viruses.
Introduction
Components of binary vector
Development of binary vector system
Properties of binary vector
Types of binary vector
Plant transformation using binary vector
Advantage of using binary vector
Conclusion
References
marker free transgenic, strategies to developed marker free transgenic, commonly used marker, Positive selection system, Negative selection system,Abiotic stress related genes as selection markers, Avoiding the use of selectable marker genes, Strategies to eliminate marker genes from transgenic, Co-transformation,Site-specific recombination, Multi-auto transformation vector, Intra chromosomal recombination system,Transposition system, screenable markers
HYBRIDIZATION & HAPLOID PRODUCTION
Introduction
WIDE HYBRIDIZATION
INTER-SPECIFIC HYBRIDIZATION
Barriers to distant hybridization
Techniques to overcome barriers
Haploids and Doubled Haploids in Plant
Production of haploids and doubled haploids
a) Induction of maternal haploids
Wide hybridization
3. In vitro induction of maternal haploids – gynogenesis
Induction of paternal haploids – Androgenesis
Production of Homozygous Diploid Plants
Application of Haploids in Plant Breeding
Importance and Implications of Anther and Pollen Culture
The isolation, culture and fusion of protoplasts is a fascinating field in plant research. Protoplast isolation and their cultures provide millions of single cells (comparable to microbial cells) for a variety of studies.
Genetic manipulation of plant and animal cells have to be confirmed for further application. One such confirmatory method is the use of stains/dyes which produces fluorescence when the recombination is successful.
A process where an embryo is derived from a single somatic cell or group of somatic cells. Somatic embryos (SEs) are formed from plant cells that are not normally involved in embryo formation.
Embryos formed by somatic embryogenesis are called Embryoids.
The process was discovered for the first time in Daucas carota L. (carrot) by Steward (1958), Reinert (1959).
What are an expression vector? Detailed description of plant gene structure. Plant expression vector systems are generally consists of Ri and Ti plasmids.
The other vectors which are generally used are DNA and RNA viruses.
Introduction
Components of binary vector
Development of binary vector system
Properties of binary vector
Types of binary vector
Plant transformation using binary vector
Advantage of using binary vector
Conclusion
References
marker free transgenic, strategies to developed marker free transgenic, commonly used marker, Positive selection system, Negative selection system,Abiotic stress related genes as selection markers, Avoiding the use of selectable marker genes, Strategies to eliminate marker genes from transgenic, Co-transformation,Site-specific recombination, Multi-auto transformation vector, Intra chromosomal recombination system,Transposition system, screenable markers
In plant and animal biotechnology, we used marker genes as selection of our GOI in host organism, but there are some problems related o these marker genes. Here we discussed about some marker free mathedologies.
Introduction
◦ The process of developing transgenic plants without the
presence of selectable markers (or) by use of more acceptable
marker genesis regarded as Clean Gene Technology.
◦ Also called “Marker Free Approach” for transgenic plant.
Need of CGT
◦ The products of some marker genes may be toxic or allergic.
◦ The antibiotic resistance might be transferred to pathogenic
microorganisms in the soil.
◦ There is a possibility of creation of superweeds that are resistant
to normally used herbicides.
Methods of CGT
◦1. Co-Transformation
◦2. Site Specific Recombination
◦3. Transposon‐Based Marker Method
◦4. Intra Chromosomal Homologous Recombination
1.Co-transformation
◦ Co-transformation is a method for production of marker free
transformants based on Agrobacterium- or biolistic mediated
transformation in which a SMG and gene of interest are on
separate constructs.
◦ SMGs can subsequently be removed from the plant genome
during segregation and recombination that occurs during sexual
reproduction by selecting on the transgene of interest and not
the SMG in progeny.
2. Site Specific Recombination
◦ Also called “mediated marker deletion”.
◦ The deletion of short, recognized DNA sequence with the activity of
recombinase enzymes has been a major step to acquire the marker free
transgenic plant.
◦ Systems for removal of marker gene
1. Cre/loxP: 2. FLP/FRT: 3. R/RS:
E.coli Bacteriophage Saccharomyces cerevisiae Zygosaccharomyces
3. Transposon‐based marker method
◦ This process is quite similar to site specific recombination where
transposons or jumping genes are used instead of a
recombination and recognition sites.
◦ Steps:
•(i) Insertion of the marker gene onto a transposon, a segment
of DNA that “hops” around in the plant’s genome;
•(ii) co-transformation with gene of interest
•(iii) Segregation of the marker gene.
4. Intrachromosomal recombination system
◦Non‐recombinase
◦ Spontaneous excision
attp: attachment P region of bacteriophage λ
ICRS
◦ Recombination sites are engineered into the plant, but no
recombinase is expressed.
◦Intrachromosomal recombination in plants is obtained by
insertion of SMG between two direct repeats of attP that
facilitates spontaneous excision.
◦ Base composition of the attP site sequence is A + T rich, which is
conjectured to play a recombination-stimulating role.
.Conclusion and future prospects
◦ The removal of marker gene from the transgenic plants supports multiple
transformation cycles for transgene pyramiding.
◦ It is clear that several viable methods for the removal of unwanted marker
genes already exist.
◦ It seems highly likely that continued work in this area will soon remove the
question of publicly unacceptable marker genes.
◦ At present there is no commercialization of marker free transgenic crop.
◦ But development of marker free transgenics would further increase the crop
improvement program.
gene cloning in eukaryotes (gene transfer).pdfNetHelix
Gene cloning recently faced difficulties associated with
bacteria, especially when dealing with
genes from eukaryotic organisms so we should to employ the eukaryotic expression in this PDF we will learn about gene cloning in eukaryotes, types of yeast plasmids and the importance of each one
systems
Genetic Transformation of Maize: Conventional Methods and Precision Geno...Ananya Sinha
Genetic Transformation of Maize: Conventional Methods and Precision Genome Modification
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Genomics, proteomics and metabolomics are the three core omics technologies, which respectively deal with the analysis of genome, proteome and metabolome of cells and tissues of an organism.
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and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
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Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
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Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
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Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
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Exposé invité Journées Nationales du GDR GPL 2024
2. TRANSGENIC PLANT
• Plants that have been genetically engineered,
an approach that uses recombinant DNA
techniques to create plants with new
characteristics.
• Also known as Genetically Modified Organism
(GMO).
• Plant developed after successful gene transfer
• Have stably integrated foreign gene
3. MARKER GENES
• Monitoring and detection of plant transformation
systems in order to know DNA successfully transferred
in recipient cells or not.
• A set of genes introduced along with the target gene
into the plasmid.
• Known as Marker genes.
• antibiotic and herbicide resistance genes successfully
used as marker genes.
• Allow the transformed cell to tolerate the antibiotic or
herbicide and regenerate into
plants while the untransformed
ones get killed.
4. Need for Marker Free Transgenics
• Marker genes generally have little agronomic value after
selection events
• Retention of the HT gene in the genome may be
problematic
• In situations requiring more transformations into cultivars
the presence of a particular marker gene in a transgenic
plant - use of the same marker in subsequent
transformation.
•Use of a different marker system is
required for each transformation round or
event.
•For public acceptance of transgenics,
keeping in mind ecological and food safety
•Marker free transgenics should be
developed.
7. The generation of transgenic plants by the
elimination of the “problematic” selectable
marker genes from the genome of the transgenic
plants or avoiding the use of selectable marker
genes in the beginning of transformation by a
marker-free vector.
MARKER FREE TRANSGENIC
8. STARATEGIES TO PRODUCE
RESISTANT MARKER‐FREE
TRANSGENIC PLANTS
• Use of screenable markers
• Co-transformation
• Site-specific recombination
• Multi-autotransformation vector
• Intrachromosomal recombination system
• Transposition system
9. SCREENABLE MARKERS
• Screenable markers encode gene products whose
enzyme activity can be easily assayed
• Can detect transformants
• Also estimation of the levels of foreign gene expression
in transgenic tissue done.
• Ex. β-glucuronidase (GUS), luciferase or β-
galactosidase genes, phytohormone metabolism
isopentenyl transferase (ipt) gene from the T-DNA of
Agrobacterium.
• Can be used to study cell-specific as well as
developmentally regulated gene expression.
10. • Involves transformation with two plasmids that target
insertion at two different plant genome loci. One
plasmid carries a SMG and the other carries the GOI
• In this system, SMG and target genes are not loaded
between the same pair of T-DNA borders.
• Instead, they are loaded into separate T-DNAs, which
are expected to segregate independently in a
Mendelian fashion.
Co-transformation Method
12. (a) Physical diagram of two T-DNA region showing gene of interest (GOI) and marker gene. (b)
Transformed calli having GOI and marker gene. (c) T0 plant having GOI and marker gene. (d) Two T1
plants one with GOI and another with marker gene.
13. • In this approach, SMG is flanked with direct repeats of
recognition sites for a site specific recombinase, which
allows the enzyme to excise the marker gene from the
plant genome by enzyme mediated site specific
recombination
• A common feature of the system is that after a first round
of transformation, transgenic plants are produced that
contain the respective recombinase and the sequence to be
eliminated between two directly oriented recognition sites.
• After expression of the single chain recombinase, the
recombination reaction is initiated resulting in transgenic
plants devoid of the selectable marker
SITE SPECIFIC RECOMBINATION
(SSR)SYSTEM
16. • A positive selection system
• Unique as it uses morphological changes caused by
oncogene [ipt gene] or rhizogene (the rol gene) of A.
Tumefaciens which control the endogenous levels of plant
hormones and the cell responses to PGR as the selection
marker
• A chosen GOI is placed adjacent to a multigenic element
flanked by RS recombination sites. A copy of the selectable
ipt gene from A.tumefaciens is inserted between these
sites
16
MAT SYSTEM
17. • Together with the R recombinase gene , entire
assembly is situated within a T-DNA element for the
Agrobacterium-mediated transformation.
• Neither antibiotic- nor herbicide-resistance genes are
necessary as a selection marker. In addition, it allows
for repeated transformation of genes of interest in a
plant (Sugita et al. 2000).
• Principle of MAT uses oncogene (ipt) for selection of
transgenic plants and a SSR system
17
MAT SYSTEM
18. Recombinase (R) catalyses
recombination between two
directly oriented recognition
sites (Rs) and removes a ‘hit
and run’ cassette from a plant
genome.
Recombinase (R) gene
expression is under the
chemically inducible promoter
(IP) in order to avoid early
removal of ipt gene.
P; promoter, T; terminator,
GOI; gene of interest, LB; left
border, RB; right border.
6/8/2015Dept. of PMBB
18
20. • The maize Ac/Ds transposable element system has
been used to create novel T-DNA vectors for
separating genes that are linked together on the same
T-DNA after insertion into plants.
• Once integrated into the plant genome, the expression
of the Ac transposase within the T-DNA can induce
the transposition of the GOI from the T-DNA to
another chromosomal location.
• This results in the separation of the gene of interest
from the T-DNA and SMG.
Transposon‐based marker methods
22. Transposon based marker free
transgenics
Fig: Schematic diagram of the Ac-Ds transposon system. (a) T-DNA region showing GOI
merged between Ac sites and marker gene, reporter gene and AcTpase region is outside the
Ac sites. (b) Diagram showing the T-DNA region having GOI merged in Ac region excised out
from marker and reporter gene.
23. An inducible transposon system to terminate the
function of a selectable marker in transgenic rice
(Tu et al., 2008)
24. Conclusion and future prospects
• The removal of marker gene from the transgenic
plants supports multiple transformation cycles for
transgene pyramiding.
• It is clear that several viable methods for the removal
of unwanted marker genes already exist.
• It seems highly likely that continued work in this area
will soon remove the question of publicly unacceptable
marker genes.
• At present there is no commercialization of marker-
free transgenic crop.
• But development of marker free transgenics would
further increase the crop improvement programme.