Ch. 21, Biotechnology

What is biotechnology?

tachnolgies that invovles the use of living organisms, their products, to benefit humans.

How do genetically modifies organisms recieve genetic material?

recombinant DNA

What does it mean to be transgenic?

an organism that has integrated recombinant DNA into its genome from a different species.

What does it mean to have transgene?

A gene from one species that is introduced into another species.

What are the falls backs of using recombinant mircoorganisms?

safety concerns and negative public perception

What was the first genetically engineered drug?

In

What is a vaccine?

contains 1 (+) comonents from a diease-causing cell to stimulate the body’s immune system

What does the immune system produce?

antibodies that recognize and destroy the component

memory cells that retain the ability to fight future infections

What is the practice of administering a vaccine?

vaccination

What are the different types of vaccine compositions"?

Whole pathogen vaccines

• inactivated vaccines

• attenuated vaccines

Subunit Vaccines

Viral Vector Vaccines

Nucleic Acid Vaccines

• DNA plasmid vaccines

• mRNA vaccines

What are whole-pathogen vaccines?

entire pathogens that have been completely inactivated or weakened

What are inactivated vaccines?

ontain a treated pathogen that cannot cause an infection (that is. influenza, hepatitis A, and rabies)

Provide short-term immunity

What are attenuated vaccines?

created by reducing the virulence of a pathogen but keeping it viable (MMR combined vaccine), chickenpox, and yellow fever.

Promote a long-lasting and strong immune response

What are subunit vaccines?

contain only certain components (proteins/ Polysaccharides) that best stimulate the immune system (only a portion of a disease-causing agent)

• Often require the addition of adjuvants, or substances that support immune response; antigens alone are not sufficient to induce adequate immunity; booster shots may be needed

What are viral vector vaccines?

use a modified version of a virus that is different from the virus that the vaccine is directed against; the viral vector could be an adenovirus, but the vaccine could be targeted against SARS-CoV-2, which causes COVID-19.

Approved for treatment against Ebola virus and SARS-CoV-2

What are nucleic acid vaccines?

involve introducing genetic material coding the protein antigen or antigens against which an immune response is sought?

What are DNA plasmid vaccines?

contain a small cicular piece of DNA (plasmid) that carriers genes coding proteins from a pathogen.

What are mRNA vaccines?

mRNA is encapsulated in a lipid nanoparticle and codes a viral spike slycoprotein usually work by introducing an mRNA

What is the mechanism of an mRNA vaccine?

mRNA coding viral spike gycoprotein encapsulated in lipid nanoparticle

Lipid nanoparticle is taken into a muscle cell

The mRNA is released into the cytosol

The mRNA is translated into a viral spike sycoprotein, which travels through the endoplasmic reticulum and Golgi apparatus to teash the plasma membrane.

What different types of vaccines commonly used for COVID-19?

nucleic acid vaccine, viral vector, subunit vaccine

What different produces created a COVID-19?

Pfizer-BioNTech, Moderna, Johnson & Johnson/Janssen, AstraZeneca/Oxford, Novovax

What are the outsomes of introducing a cloned gene into a cell?

gene modification (gene editing, alters the sequnce of a gene)

gene addition (genes can be added from different species to produce a transgeneic organism)

What proteins that are produced in domesticaed animal milk are used for molecular pharming?

lactoferrin, tissue plasminogen activator, antibodies, alpha₁ - antitrypsin, Factor IX, insulin-like growth factor

What is the procedure for expressing human genes in animal milk?

Human gene coding a protein of value (as in the previous table) is inserted in a plasmid vector next to a milk specific promoter.

DNA is then injected into sheep oocyte and integrates into the genome

Fertilized oocyte implanted in sheep uterus, which then gives birth to a transgenic sheep offspring

Female offspring secretes human protein in milk

Purify protein from milk

What does reporoductive cloning produces?

2(+) genetically identical individuals

Which is easier to reproductively clone, plants or animals?

plants; they are easier; they are cut and exposed to hormones

What are the aging results of cloned animals

• shortened telomeres, resulting from the somatic cells of the donor sheep

• premature aging?

What is the recent success in cloning?

• cloning of somatic cells have been achieved in several mammalian species

• Farmers can use somatic cells from thei best individuals to create genetically homogeneous herds, which is advantageous to agricultural yield but the overall herd may by more susceptible to rare diaseses.

What are stem cells?

they supply the cells that construct out bodies from a ferilzed egg.

In adults, stem cells can also replenish damanged cells

They have the capacity to divide and differentiate into one of more specialized cell types

What are the different types of stem cells?

Totipotent cells: fertilzed eggs, can give rise to ALL cell types and an entire individual

Pluripotent cells: can differentiate into almost every cell type, but can’t give rise to an entire individual

• ES cells

• EG cells

Multipotent cells: can differentiate into several cell types

Unipotent cells: can only differentiate into one cell type

What do stem cells have the potenitial to treat?

diseases/injuries that cause cell and tissue damage

ex) bone marrow transplants to treat certain forms of cancer, BUT, they are rare… 1 cell in 10,000 in the bone marrow is a stem cell.

What is induced pluripotent stem cells (iPS cells)?

cells that could differentiate into all cell types when injected into mouse blastocysts

What are the potential uses of stem cells to treat diseases?

1. Neural cells // implantation of cells into the brain to treat Parkinsons disease. Treatment of injuries such as those to spinal cord.

2. Skin cells // treatment of burns or other types of skin disorders

3. Cardiac cell // repair of heart damage associated with heart attacks

4. Cartilage cell// repair of joints damaged by injury or arthritis

5. Bone cells // repair of damaged bone or replacement with new bone

6. Liver bone // repair or replacement of liver tissue that has been damaged by injury or disease

7. skeletal muscle // repair or replacement of damaged muscle

When plasmid DNA (that carries the transgene) is injected into oocytes (see Fig. 21.5), only a small number of oocytes (<5%) actually integrate the plasmid DNA into the genome. Which of the following methods is the easiest to screen hundreds of offspring for the presence of transgene ? Note that you are allowed to collect only a small amount of blood for this purpose.

PCR

RT-PCR

Northern blot

Western blot

PRC

When transgenic animals are made by gene addition method (see Fig. 21.5), the transgene is randomly integrated into the host genome. The integration site may influence the expression of the transgene. Pick one technique that would NOT be appropriate to test transgene expression.

PCR

RT-PCR

Northern blot

Western blot

PCR

Which of the following techniques does NOT use recombinant DNA technology?

Production of medicines using bacterial cells

Production of medicines using livestock

A reporter assay using the LacZ gene

Reproductive cloning

reproductive cloning