Name: creating transgenic plants and animals
Uploaded: 2026-08-26T08:20:38.604Z
Duration: 1 min 26 s
Channel: JoVE

K12 Standards

Georgia Standards of Excellence

9-12

Biology

SB2.c

Transgenic Organisms

- [Narratore] Organismi transgenici

sono geneticamente modificati
per avere un transgene,

un nuovo gene, spesso di un&#x27;altra specie,

inserito nel loro genoma

in modo che possa produrre
la proteina desiderata.

Ad esempio, le capre transgeniche
sono state sviluppate

per produrre seta di ragno nel loro latte,

che viene poi utilizzato per fabbricare

fibre eccezionalmente forti.

L&#x27;introduzione del transgene &#xE8; tipicamente

fatta nella prima fase di sviluppo,

come l&#x27;uovo fecondato,

in modo che finisca in tutte
le cellule dell&#x27;organismo,

comprese le cellule sessuali,

chiamate anche cellule germinali.

L&#x27;incorporazione in queste
cellule permette al transgene

di essere trasmesso di generazioni
attraverso l&#x27;allevamento,

creando una linea di organismi transgenici

che producono le proteine estranee.

Wheeler, M.B. 2013. "Animali transgenici in agricoltura". Conoscenza dell'educazione alla natura 4 (11): 1. [<a href="https://www.nature.com/scitable/knowledge/library/transgenic-animals-in-agriculture-105646080" target="__blank">Sorgente</a>]

Yao, Jian, Yunqi Weng, Alexia Dickey e Kevin Yueju Wang. 2015. "Piante come fabbriche di prodotti farmaceutici per uso umano: applicazioni e sfide". Giornale internazionale di scienze molecolari 16 (12): 28549–65. [<a href="https://doi.org/10.3390/ijms161226122" target="__blank">Sorgente</a>]

organismi transgenici

<h4>Panoramica</h4>

Gli organismi transgenici sono geneticamente progettati per trasportare transgeni, geni di una specie diversa, come parte del loro genoma. Il transgene pu&#xF2; essere una versione diversa di uno dei geni dell&#x27;organismo o un gene che non esiste nel loro genoma. I transgeni sono di solito generati da tecniche ricombinanti di DNA e clonazione del DNA. Batteri, piante e animali transgenici consentono agli scienziati di affrontare richieste biologiche e progettare soluzioni pratiche.

<h4>Creazione di un organismo transgenico</h4>

Gli scienziati iniziano il processo di transgenesi, introducendo un transgene nel genoma di un organismo, selezionando una tecnica appropriata. Ci sono diversi metodi biologici, chimici e fisici della transgenesi. Un metodo biologico comune prevede l&#x27;introduzione mediata dal virus del DNA estraneo in un genoma della cellula ospite, chiamato trasduzione. Un metodo chimico popolare utilizza fosfato di calcio (Ca3(PO4)2). Il metodo si basa sulla formazione di un precipitato Ca3(PO4)2/DNA per facilitare il legame del DNA e l&#x27;ingresso delle cellule. Metodi fisici come la microiniezione, una tecnica che utilizza un ago sottile di vetro per inserire manualmente materiale genetico nelle cellule, introducono artificialmente il DNA con la forza.

Una volta all&#x27;interno della cellula, un transgene pu&#xF2; integrarsi in modo casuale o in un sito specifico del genoma con l&#x27;aiuto di enzimi di riparazione del DNA (cio&#xE8; ricombinazione). Queste cellule transgeniche poi si moltiplicano e replicano il transgene come parte del loro genoma, esprimendo stabilmente il gene di interesse del ricercatore. Un transgene potrebbe non integrarsi nel genoma, e quindi indurre solo l&#x27;espressione transitoria del gene di interesse del ricercatore. Di solito, un marcatore selezionabile (ad esempio, gene di resistenza agli antibiotici) o un gene reporter (ad esempio, GFP) sono inclusi insieme al gene di interesse, in modo che le cellule con successo dell&#x27;integrazione transgenica possano essere identificate.

<h4>I transgeni possono essere introdotti in animali e piante</h4>

Negli animali, il transgene viene tipicamente inserito in un uovo fecondato in fase iniziale mediante microiniezione. La speranza &#xE8; che il transgene si integri nelle cellule germinali ( cellule precursori riproduttive che diventano gameti (cio&#xE8;, uova o spermatozoi) in modo che esprima in tutte le cellule dell&#x27;organismo in via di sviluppo. Inoltre, l&#x27;integrazione germinale &#xE8; ereditabile, il che significa che il transgene pu&#xF2; essere tramandato di generazione in generazione mediante l&#x27;allevamento. Gli animali transgenici vengono incrociati- la prole &#xE8; accoppiata con il genitore - per creare linee di animali omozigotici per il transgene.

La transgenesi vegetale utilizza regolarmente un metodo biologico, come la somministrazione di vettori batterici, per introdurre il DNA estraneo nelle cellule. Il rhizobium radiobacter (precedentemente noto come Agrobacterium tumefaciens) &#xE8; un batterio patogeno che pu&#xF2; infettare le piante e integrare il suo DNA plasmide nel genoma della pianta. Gli scienziati hanno modificato il radiobacter R. in modo che il DNA del plasmide possa trasportare un transgene. I campioni di tessuto vegetale sono coltivati con il radiobacter R. per consentire l&#x27;infezione e l&#x27;integrazione del transgene. Questi tessuti sono ulteriormente coltivati su supporti selettivi che inducono il tiro e la crescita delle radici fino a quando la pianta nascente pu&#xF2; essere trasferita al suolo. Queste piante transgeniche sono riincrociate per creare linee di piante transgeniche ad alta resa.

<h4>Usi pratici di organismi transgenici</h4>

Gli organismi transgenici hanno molte applicazioni in agricoltura, scienza, industria e medicina. Ad esempio, sono state prodotte piante transgeniche resistenti agli insetti per aumentare la resa e ridurre l&#x27;uso di pesticidi (ad esempio, mais Bt); batteri sono stati progettati per l&#x27;uso nella ricerca biomedica e per la produzione di biocarburanti; e gli animali transgenici sono stati utilizzati per produrre farmaci, come le proteine umane, e per creare modelli di malattie umane. Gli scienziati sfruttano il potere di piante, batteri e animali transgenici per ricercare l&#x27;espressione genica, creare prodotti genici desiderati o promuovere tratti preziosi.

Organismi transgenici

Overview

Transgenic organisms are genetically engineered to carry transgenes&#x2014;genes from a different species&#x2014;as part of their genome. The ...

https://cloudfront.jove.com/files/ftp_upload/10809/10809_article_thumb_10809.jpg

Education

Didattica

JoVE Core

Biologia

Genetics

Genetica

Biotechnology

Biotecnologia

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

creating transgenic plants and animals

Transgenic organisms are genetically engineered to carry a transgene, which is a gene from a different species, in their genome. The inserted gene may be a new gene for that organism or a different version of one it already has. Scientists usually make transgenes with recombinant DNA and DNA cloning methods.

Researchers use transgenic bacteria, plants, and animals to answer biological questions and to build useful tools. To make a transgenic organism, they first choose a transgenesis method, which is the process of adding a transgene to a genome. Common methods include biological, chemical, and physical approaches.

One biological method is transduction, where a virus carries foreign DNA into a host cell genome. A chemical method uses calcium phosphate, or Ca3(PO4)2, to form a precipitate with DNA that helps the DNA bind to cells and enter them. A physical method is microinjection, which uses a thin glass needle to push genetic material directly into cells.

After DNA enters the cell, the transgene may integrate randomly or at a specific site with help from DNA repair enzymes through recombination. The transgenic cells then divide and copy the transgene as part of their genome. In some cases, the transgene does not integrate, so it only gives temporary expression of the gene of interest.

Scientists often add a selectable marker, such as an antibiotic resistance gene, or a reporter gene, such as GFP, with the gene of interest. These extra genes help identify cells that successfully took up the transgene. In animals, the transgene is usually microinjected into an early fertilized egg so it can enter germ cells, the precursor cells that form egg or sperm.

If the transgene reaches the germ line, it can be expressed in the developing organism and passed to later generations through breeding. Transgenic animals are often backcrossed, which means the offspring are mated with the parent, to make homozygous lines. In plants, scientists often use Rhizobium radiobacter, a soil bacterium formerly called Agrobacterium tumefaciens, to deliver plasmid DNA carrying the transgene into plant cells.

Plant tissues are cultured with R. radiobacter so the bacteria can infect the cells and insert the transgene into the plant genome. The tissues are then grown on selective media that promote shoot and root growth until the new plant can be moved to soil. These transgenic plants are also backcrossed to produce high-yield lines.

Transgenic organisms have many uses in agriculture, science, industry, and medicine. Transgenic plants can be made insect-resistant, such as Bt corn, to raise yield and reduce pesticide use. Engineers also create transgenic bacteria for biomedical research and biofuel production, and transgenic animals can produce medicines, including human proteins, or serve as models of human disease.

Creating Transgenic Plants and Animals

what is genetic engineering?

How Scientists Edit DNA for New Traits

Genetic engineering changes an organism’s DNA to add useful traits. Scientists use it in bacteria, plants, animals, and even viruses for research, medicine, agriculture, and industry. It can bring major benefits, but it also raises ethical concerns about humans and the food supply. This work is possible because DNA has the same basic structure and genetic code across life. That shared code lets scientists modify DNA in several ways. One method is CRISPR/Cas9, often called molecular scissors,...

dna isolation

Steps in DNA Extraction

DNA extraction is the process of removing and purifying DNA from cells. It is used in many biotechnology and research applications, including molecular cloning. The main goal is to free DNA from the cell and prepare it for later study or use. The first step is cell lysis, which means breaking cells open. Researchers may use a homogenizer, sonicator, or bead beater to physically lyse the cells. They also often add detergent to chemically disrupt the lipid-based cell membranes. This helps...

recombinant dna technology

Recombinant DNA in Cloning and GMOs

Recombinant DNA is made by joining DNA from different sources in the lab. Scientists often use it to clone genes and study them in cells that are easy to handle, such as bacteria. Organisms that carry recombinant DNA are called genetically modified organisms, or GMOs. This technology gives scientists new tools for research, medicine, and agriculture. To build recombinant DNA, researchers place a gene of interest into a vector, which is a DNA carrier that moves foreign DNA into a host cell. The...

PCR Cycle for DNA Amplification

PCR is a laboratory method for making many copies of a DNA segment. It can turn a small amount of DNA into millions or even billions of copies in just a few hours. The process uses a heat-resistant DNA polymerase inside a machine called a thermocycler. PCR was developed by Kary Mullis in 1983, and he received the 1993 Nobel Prize in Chemistry for it. The method is fast, relatively inexpensive, and precise. It has become useful for molecular cloning, gene mutagenesis, pathogen detection, gene...

complementary dna

From mRNA to cDNA for Gene Studies

Complementary DNA, or cDNA, is made from messenger RNA (mRNA) so scientists can study which genes are active in cells and tissues. Only genes that are transcribed into mRNA are expressed. By extracting mRNA from cells, researchers can compare gene expression across samples. cDNA is produced by reverse transcription. This process copies mRNA into DNA, which is useful because mRNA does not contain introns, or non-coding regions, and other regulatory sequences. As a result, cDNA can help...

antibiotic selection

Antibiotic Resistance in Cloning

Antibiotic resistance genes help scientists find bacteria that took up a plasmid with a gene of interest. In genetic engineering, this resistance is used as a marker, not just as a medical concern. The same process also connects to the growing problem of resistant bacteria in the real world. Antibiotics, such as penicillin, stop bacterial growth or kill bacteria. When bacteria naturally have, or are engineered to carry, an antibiotic resistance gene, the antibiotic no longer works on them.

transgenic organisms

Transgenic organisms are genetically engineered to carry a transgene, which is a gene from a different species, in their genome. The inserted gene may be a new gene for that organism or a different version of one it already has. Scientists usually make transgenes with recombinant DNA and DNA cloning methods. Researchers use transgenic bacteria, plants, and animals to answer biological questions and to build useful tools. To make a transgenic organism, they first choose a transgenesis method,...

in-vitro mutagenesis (gene knockouts)

Knockout Mice and Gene Replacement

Knockout mice help researchers study gene function by showing what happens when a gene is turned off. These engineered animals are also useful for modeling human diseases such as cancer, Parkinson’s disease, and diabetes. A specific gene can be targeted by using a targeting vector, which is a piece of engineered DNA that replaces the normal gene and inactivates it. The vector has matching DNA sequences on both ends. These homologous sequences let the vector swap in for the target gene through...

crispr

CRISPR-Cas9 Gene Editing in Action

CRISPR-Cas9 is a genome editing tool that lets scientists change DNA at a specific location. It can add, remove, or rearrange genetic material. Researchers study it because it may help treat genetic disorders such as hemophilia and sickle cell anemia. CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats, and Cas9 is a CRISPR-associated protein 9. The basic system includes a Cas9 endonuclease, which is an enzyme that cuts DNA, and a small RNA that guides Cas9 to the...

gene therapy

Gene Delivery for Serious Diseases

Gene therapy is a technique used to treat serious disease by adding a gene to a person’s cells. The added gene may be a healthy copy of a mutated gene. It may also be a different gene that inactivates or compensates for the disease-causing gene. One example is severe combined immunodeficiency, or SCID, caused by a mutation in the gene for adenosine deaminase. In that case, a working copy of the gene can be inserted so the patient’s cells make the enzyme again. This can cure the disease in some...

embryonic stem cells

How Embryonic Stem Cells Become Specialized

Embryonic stem cells are pluripotent cells that have not yet specialized. Pluripotent means they can give rise to many different cell types in the body. Because of this, they are useful in science and medicine for making cells needed in research or for replacing cells lost to damage or disease. These cells come from the inner cell mass of a blastocyst, which is an early embryo about 3 to 5 days after fertilization in humans. At this stage, the embryo has not yet implanted in the uterus. Human...

adult stem cells

Adult Stem Cells in the Small Intestine

Adult stem cells help maintain tissues by replacing old or damaged cells. These undifferentiated cells divide to make more stem cells or progenitor cells, which then become mature, specialized cells. Small groups of adult stem cells are found in many tissues, including the bone marrow, brain, skin, and gut. The small intestine shows this process clearly. Its lining, called the epithelium, is renewed continuously by adult stem cells. It is also the fastest replaced tissue in the human body,...

induced pluripotent stem cells

Reprogramming Mature Cells into Stem Cells

Reprogramming mature cells into stem cells lets scientists turn specialized cells back into an unspecialized state. These cells are called induced pluripotent stem cells, or iPSCs. Like embryonic stem cells, iPSCs are pluripotent, which means they can form all cell types. To make iPSCs, researchers start with mature cells such as skin fibroblasts or blood cells. The cells are grown in culture, and genes for several transcription factors are delivered with a viral vector. The cells then make...

reproductive cloning

Cloning Animals with SCNT

Reproductive cloning can produce a genetically identical copy of an entire organism. In adult animals, this is usually done with somatic cell nuclear transfer, or SCNT. Another way clones can form is by splitting an early embryo, which is similar to how identical twins arise naturally. In SCNT, an egg cell is taken from an animal and its nucleus is removed. This creates an enucleated egg. A somatic cell, which is any body cell that is not a sex cell, is then taken from the animal to be cloned.

genomics

Genomics and DNA Sequencing

Genomics studies the full set of genetic material in an organism. In humans, that genome includes the DNA carried in 23 pairs of chromosomes in the nucleus, along with mitochondrial DNA. Genomics looks at both coding DNA and non-coding DNA, which helps scientists study how living things are built and how they differ. This field is useful in many areas of biology and medicine. Scientists use genomics to build phylogenetic trees, improve crop productivity and sustainability, help with criminal...

key terms and concepts

Learn how scientists make transgenic plants, bacteria, and animals using microinjection, bacteria, and other methods to study genes and create useful traits.

Creating Transgenic Plants and Animals | JoVE K12

JoVE Core series brings biology to life through over 300 concise and easy-to-understand animated video lessons that explain key concepts in biology, plus more than 150 scientist-in-action videos that show actual research experiments conducted in today’s laboratories.

biology

JoVE Core Biologia illustra i concetti chiave della biologia grazie a oltre 300 video-lezioni animate, concise e di facile comprensione. Inoltre, negli oltre 150 video di "scienziati in azione", i concetti scientifici vengono applicati e dimostrati da ricercatori attraverso esperimenti in laboratorio.

The Central Dogma

Replication in Eukaryotes

Types of RNA

Transcription

Translation

regulation-of-expression-at-multiple-steps

Regulation of Expression at Multiple Steps

The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. ...

Construct an explanation of how the structures of DNA and RNA lead to the expression of information within the cell via the processes of replication, transcription, and translation

SB2.a

What is Meiosis?

Meiosis I

Meiosis is the division of a diploid cell into haploid cells forming sperm and eggs in animals through differentiation. Meiosis I is the first stage of ...

Meiosis II

Meiosis II entails cell division and segregation of the sister chromatids, resulting in the production of four unique haploid gametes. The steps for ...

Crossing over

Nondisjunction

Genome Copying Errors

DNA replication is a well-evolved process that copies millions of base pairs with high fidelity during each cell division. Occasionally a wrong base or a ...

Overview of DNA Repair

In order to be passed through generations, genomic DNA must be undamaged and error-free. However, every day, DNA in a cell undergoes several thousand to a ...

Base Excision Repair

One of the common DNA damages is the chemical alteration of single bases by alkylation, oxidation, or deamination. The altered bases cause mispairing and ...

RNA Editing

RNA editing is a post-transcriptional modification where a precursor mRNA (pre-mRNA) nucleotide sequence is changed by base insertion, deletion, or ...

Mutations

Teratogenicity

The ability of a drug to produce structural deformations and functional abnormalities in the developing embryo or the fetus is called teratogenicity, and ...

Mechanisms of Retrovirus-induced Cancers

Retroviruses are RNA viruses that have been shown to cause cancers in diverse species, including chickens, mice, cats, and monkeys. The RNA genomes of ...

Construct an argument based on evidence to support the claim that inheritable genetic variations may result from:New genetic combinations through meiosis (crossing over, nondisjunction), Non-lethal errors occurring during replication (insertions, deletions, substitutions), Heritable mutations caused by environmental factors (radiation, chemicals, and viruses)

SB2.b

Transgenic Plants

Recombinant DNA technology called transgenesis is often used to add a foreign gene or remove a detrimental gene from an organism. Such genetically ...

Testing For Genetically Modified Foods

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University
Genetic modification of foods has been a controversial issue due to debated ...

Genetic Engineering of Model Organisms

Transgenesis, or the use of genetic engineering to alter gene expression, is widely used in the field of developmental biology. Scientists use a number of ...

Ask questions to gather and communicate information about the use and ethical considerations of biotechnology in forensics, medicine, and agriculture

Obtain, evaluate, and communicate information to analyze how genetic information is expressed in cells

Creating Transgenic Plants and Animals

Description

Transcript

Tags

More videos by Standards