Genetic Engineering

Summary

This educational video delves into the fascinating world of genetic engineering, illustrating how DNA from a cat and a jellyfish can be combined to create a glow-in-the-dark cat. It explains key concepts like gene splicing, recombinant DNA, and genetic modification, using accessible language. The video outlines the process involving enzymes like restriction enzymes and ligase, which cut and rejoin DNA, respectively. It also covers the use of bacteria as 'factories' for producing human insulin, showcasing the potential of genetic engineering in medicine and beyond.

Takeaways

• 🌟 Genetic engineering involves the manipulation of an organism's genes using biotechnology, often referred to by terms like gene splicing, recombinant DNA, or genetic modification.
• 🐱 The example of glow-in-the-dark cats illustrates how a gene from a jellyfish can be introduced into a cat's DNA to give it the ability to glow in the dark.
• 🔬 The universality of the genetic code allows for the combination of DNA from different organisms, enabling scientists to create recombinant DNA.
• ✂️ Restriction enzymes, acting like molecular scissors, cut DNA at specific sequences, creating 'sticky ends' that facilitate the joining of DNA fragments.
• 🧬 DNA ligase is an enzyme that 'glues' DNA fragments together by sealing the sugar-phosphate backbones, creating stable recombinant DNA.
• 🧬 Genetic engineering protocols often use bacteria as hosts for producing proteins, such as human insulin, due to their ease of genetic manipulation and rapid reproduction.
• 📦 Plasmids, small loops of DNA in bacteria, are particularly useful in genetic engineering because they can be easily moved in and out of bacterial cells.
• 🌱 Genetic engineering has a wide range of applications, including creating pesticide-resistant plants, bacteria that can clean up toxic waste, and producing medically important proteins.
• 💉 The process of inserting a gene into a bacterial cell and allowing it to reproduce to produce a desired protein, like human insulin, is known as transformation.
• 🏭 The final step in genetic engineering often involves isolating the produced protein from the host organism, which can then be used for various medical or industrial purposes.

Q & A

What is genetic engineering and what are some of its alternative names?

Genetic engineering is the process of taking DNA from one organism and combining it with another to create recombinant DNA. It is also known as gene splicing, recombinant DNA, or genetic modification.

How does the glow-in-the-dark cat example illustrate genetic engineering?

The glow-in-the-dark cat is an example of genetic engineering where a gene from a jellyfish that allows it to glow in the dark was combined with the cat's DNA, resulting in a cat that can also glow in the dark.

Why is the genetic code considered universal?

The genetic code is considered universal because all organisms, despite their differences, are made up of the same basic building blocks represented by the letters A, T, C, and G, allowing for the combination of DNA from different organisms.

What role do restriction enzymes play in genetic engineering?

Restriction enzymes act like scissors in genetic engineering, cutting DNA at specific sequences to create fragments that can be manipulated and recombined with DNA from other sources.

What is a sticky end and how does it contribute to genetic engineering?

A sticky end is an uneven DNA sequence created by the cutting action of a restriction enzyme. It allows for the easy binding of DNA fragments through complementary base pairing, which is crucial for combining DNA from different sources.

What is the function of ligase in genetic engineering?

Ligase is an enzyme that helps glue DNA back together by attaching the sugar-phosphate backbones, which are more difficult bonds to make, thus sealing the recombinant DNA.

How is recombinant DNA created using restriction enzymes and ligase?

Recombinant DNA is created by cutting DNA from different sources with the same restriction enzyme to produce compatible sticky ends, which then bind together. Ligase is then used to seal the sugar-phosphate backbones, creating a stable recombinant DNA molecule.

Why are bacteria often used in genetic engineering?

Bacteria are used in genetic engineering because they have plasmids, which are loops of DNA that can be easily moved in and out of cells, and they reproduce asexually, allowing for rapid production of identical bacterial cells for use as 'factories'.

How is human insulin produced using genetic engineering in bacteria?

Human insulin is produced by inserting the human insulin gene into a bacterial plasmid, creating recombinant DNA. This is then introduced back into the bacteria, which reproduce to create millions of cells containing the human insulin gene. These bacteria are then used to produce human insulin.

What are some other applications of genetic engineering mentioned in the script?

Other applications of genetic engineering include creating pesticide-resistant plants, bacteria that can clean up toxic waste, producing proteins to dissolve blood clots, making growth hormone, and even acid-washed genes.

What is transformation in the context of genetic engineering?

Transformation in genetic engineering refers to the process of introducing new DNA into a cell, which then incorporates this DNA into its genome, potentially altering its traits or functions.

Outlines

00:00

🌟 Genetic Engineering Explained

This paragraph introduces the concept of genetic engineering, also known as gene splicing, recombinant DNA, or genetic modification. It explains how DNA from one organism can be combined with another to create recombinant DNA. The process involves taking a gene from a jellyfish that allows it to glow in the dark and combining it with a cat's DNA. The key point is that the genetic code is universal, allowing for the combination of DNA from different organisms. Two types of enzymes are crucial in this process: restriction enzymes, which act like scissors to cut DNA at specific sequences, and ligase, which glues DNA back together. Restriction enzymes create 'sticky ends' that can bind to other DNA fragments with complementary sequences, facilitating the creation of recombinant DNA.

05:03

🧬 Creating Human Insulin with Bacteria

This paragraph delves into a practical application of genetic engineering: using bacteria as factories to produce human insulin. Bacteria are chosen for this purpose due to their simple genetic structure, which includes plasmids that can be easily manipulated, and their rapid asexual reproduction, allowing for the quick creation of millions of identical bacterial cells. The process involves extracting the plasmid from the bacterium and the insulin gene from human DNA, cutting both with the same restriction enzyme to create compatible sticky ends. These are then combined and sealed with ligase to form recombinant DNA, which is introduced back into the bacterium through a process called transformation. The bacteria, now containing the human insulin gene, reproduce to create a large number of cells capable of producing human insulin. This insulin can then be extracted and used to treat diabetics, demonstrating the power of genetic engineering in medicine.

Keywords

💡Genetic Engineering

Genetic engineering refers to the scientific process of altering the genetic makeup of an organism by introducing, removing, or modifying specific genes. In the video, genetic engineering is used to create a glow-in-the-dark cat by introducing a gene from a jellyfish into a cat's DNA. This process exemplifies the broader theme of the video, which is the manipulation of genetic material to achieve desired traits in organisms.

💡Gene Splicing

Gene splicing, also known as recombinant DNA technology, involves cutting and joining pieces of DNA from different sources to create a new combination of genes. This term is synonymous with genetic engineering and is highlighted in the video as a method to combine a cat's DNA with a jellyfish gene to enable the cat to glow in the dark.

💡Recombinant DNA

Recombinant DNA is the result of combining DNA from different sources to create a new DNA sequence. The video explains how recombinant DNA is created by cutting DNA from a cat and a jellyfish with the same restriction enzyme and then using ligase to join the sticky ends, resulting in a DNA sequence that contains traits from both organisms.

💡Universal Genetic Code

The universal genetic code is the concept that all living organisms use the same set of nucleotide sequences (A, T, C, and G) to encode genetic information. This allows for the possibility of genetic engineering across different species, as mentioned in the video, where DNA from a cat can be combined with DNA from a jellyfish.

💡Restriction Enzyme

Restriction enzymes, also known as molecular scissors, are enzymes that recognize and cut DNA at specific sequences. In the video, they are crucial for the genetic engineering process, as they are used to cut the DNA of the cat and the jellyfish at specific sites to facilitate the combination of their genes.

💡Ligase

Ligase is an enzyme that joins DNA fragments together. In the context of the video, after the DNA from the cat and jellyfish is cut and the sticky ends are formed, ligase is used to glue the DNA back together, creating recombinant DNA.

💡Sticky Ends

Sticky ends are the overhanging single-stranded DNA sequences created when a restriction enzyme cuts DNA unevenly. These ends are 'sticky' because they can bind to other DNA fragments with complementary sequences, which is essential for the process of creating recombinant DNA as described in the video.

💡Transformation

Transformation is the process of introducing foreign DNA into a cell. In the video, transformation is used to describe the step where the recombinant plasmid containing the human insulin gene is introduced into a bacterial cell, enabling it to produce human insulin.

💡Plasmid

A plasmid is a small, circular DNA molecule found in bacteria that is separate from the chromosomal DNA and can replicate independently. In the video, plasmids are used as vectors to carry the human insulin gene into bacterial cells, allowing for the mass production of human insulin.

💡Human Insulin

Human insulin is a hormone produced by the pancreas that regulates blood sugar levels. In the video, genetic engineering is used to create bacteria that can produce human insulin, which can then be harvested and used to treat diabetics who require insulin injections.

💡Genetic Modification

Genetic modification is the alteration of an organism's genetic material to introduce new traits or enhance existing ones. The video discusses genetic modification as a means to create glow-in-the-dark cats and bacteria that can produce human insulin, showcasing the potential applications of this technology.

Highlights

Genetic engineering enables the creation of glow-in-the-dark cats through the addition of a gene from jellyfish.

Genetic engineering is also known as gene splicing, recombinant DNA, or genetic modification.

The process involves combining DNA from different organisms to create recombinant DNA.

All organisms share a universal genetic code, allowing for the combination of DNA from different species.

Enzymes play a crucial role in genetic engineering, particularly restriction enzymes and ligases.

Restriction enzymes act like molecular scissors, cutting DNA at specific sequences.

Ligases are enzymes that 'glue' DNA fragments back together.

Restriction enzymes often create 'sticky ends' that facilitate the joining of DNA fragments.

The process of creating recombinant DNA involves cutting and pasting DNA from different sources.

Recombinant DNA is useless until it is inserted into an organism to produce the desired trait.

Bacteria are often used in genetic engineering due to their ease of genetic manipulation and rapid reproduction.

Plasmids, small loops of DNA in bacteria, are used to insert and express foreign genes.

The human insulin gene can be inserted into bacteria to produce human insulin through genetic engineering.

Genetic engineering allows for the mass production of human insulin using bacterial cells.

The process of inserting recombinant DNA into a cell is known as transformation.

Genetic engineering has applications beyond medical uses, including creating pesticide-resistant plants and cleaning up toxic waste.

The video discusses various applications of genetic engineering, showcasing its broad impact on science and medicine.

Transcripts

these cats can glow in the dark now is

this a naturally occurring trait due to

a random mutation nope this is an

example of genetic engineering and we're

going to take a look at how this process

works in this video note that genetic

engineering goes by different names you

might also hear it called gene splicing

recombinant DNA or genetic modification

but all of these terms mean the same

thing which is basically

this taking DNA from one organism

combining it with another organism and

getting recombinant DNA DNA from two

different sources now in the case of our

glow-in-the-dark cat most of the DNA

came from the cat but it received a gene

from a jellyfish that allowed it to glow

in the

dark now you might be wondering how is

it possible to combine DNA from a cat

with DNA from a jelly fish those are two

really different organisms well the key

is that the genetic code is universal so

if we were to take a look at the DNA of

this animal the DNA of this bacteria and

the DNA of this little boy we would see

some differences but they're all made up

of a T C and G now the sequence might be

different but they're speaking the same

language and because the genetic code is

universal we can combine DNA from

different organisms and genetic Eng

engineering is a

reality genetic engineering relies on

enzymes two types in particular so let's

take a few minutes to see the role of

these enzymes in genetic

engineering one of these enzymes kind of

acts like scissors it's known as a

restriction enzyme and its job is to cut

DNA at particular sequences and then

there's another enzyme known as liase

and its job is to glue DNA back

together now let's explore restriction

enzymes in a little bit more detail

there are many many different

restriction enzymes thousands and each

enzyme is specific for a particular DNA

sequence so this restriction enzyme will

only cut DNA when it sees the sequence

CC TG G this enzyme will only cut DNA

when it sees the sequence TT CG AA and

this enzyme will only cut DNA when it

sees the sequence CC ta GG you get the

idea the other thing to know about

restriction enzymes is that many of them

cut

unevenly um and this is known as the

restriction site so let's take a closer

look at how the Restriction enzyme Cuts

unevenly here's a DNA sequence here is

the restriction site for a particular

enzyme it likes to start cutting here

but then finish cutting here so what

happens is that we get an uneven DNA

sequence these uneven DNA sequences are

known as sticky ends and they're sticky

ends because since there's only one DNA

sequence exposed here it can easily bind

through complimentary base pairing rules

to another sticky end and this is

important to genetic engineering

so here we've got our sticky

ends now let's take a look at how we

would use these two enzymes together uh

to create recombinant DNA so here's our

DNA sequence here's a restriction site

for a particular restriction enzyme

first thing we're going to do is add a

restriction enzyme to cut it into

fragments there we go and here you can

see the sticky ends now we're going to

add DNA from another source that's also

also been cut using the same enzyme and

this is important because using the same

enzyme means that you get the same

sticky ends so here's DNA from one

organism here's DNA from a different one

but same sticky ends now these fragments

are going to stick together because of

complimentary base pairing so here we go

this sticky end was complimentary to

this sticky end and this sticky end was

complimentary to this sticky end so they

naturally came together however we need

a little Li at this point because liase

will help attach the sugar phosphate

backbones which are more difficult bonds

to make so once ligase gets involved

here we go we now have our recombinant

DNA DNA from one organism combined with

DNA from another

organism so this is how we would put two

different genes together but at this

point pretty useless all we have is a

recombinant DNA molecule in order for

that to actually build a protein that

makes a trait we need to put this DNA

into an organism so now let's take a

look at the whole genetic engineering

protocol and we're going to use a

particular example a very commonly used

example of genetic

engineering and this example involves

the use of bacteria to be human insulin

factories that's right because of

genetic engineering we can make

bacterial cells produce insulin that's

not bacterial insulin that's human

insulin and then we can bottle that

insulin and give it to diabetics so

here's how it works first of all let's

start with the bacterium why would we

use a bacterium as a human insulin

Factory well one reason has to do with

its genetic structure bacteria have a

big circular chromosome but then they

also have these smaller Loops of DNA

called plasmids and it's very easy to

move plasmids into and out of cells so

that's one advantage to using back

bacteria the other Advantage is that

bacteria are unicellular and they

reproduce asexually which means that in

a very short amount of time you can get

millions and millions of identical

bacterial cells clones and this is

important if you want

factories so let's see how the

experiment Works we're going to start

with um our eoli bacterium here you can

see its chromosome here you can see its

plasmid and then we've got a human cell

and this human cell contains a nucleus

which contains DNA and within that DNA

is a gene for producing insulin now this

is the correct Gene this produces good

insulin so the first thing we're going

to do is we're going to take the

plasmine out of the bacteria and we're

going to take the DNA out of the human

cell easy

enough then we're going to cut both of

them with the same restriction enzyme so

here the plasmid has been cut and here

the human DNA has been cut and we're

going to use a restriction enzyme that

cuts at sights around the human insulin

Gene so it's important to pick the right

restriction enzyme for your experiment

so now we have our human insulin Gene

and we've got our cut plasmid now we're

going to combine those two together and

because of complimentary base pairing

and because of the sticky ends they're

going to naturally bond together

then we're going to throw in a little

bit of liase to help seal the sugar

phosphate backbones and now we have our

recombinant DNA most of the plasmid is

bacterial DNA but it now has the human

insulin Gene pretty cool but again this

is useless unless we put it inside a

cell so that the DNA can be used to make

the protein insulin so let's do that

next step number seven we're going to

stick this reconvened plasmid back into

the bacterial cell and this process is

known as transformation whenever you

give a cell new DNA it's called

transformation so now we're going to let

this bacteria cell reproduce and in a

matter of days we'll have millions and

millions and millions of identical

bacteria all of them with this

recombinant plasmid that contains the

gene for human insulin so we're going to

let these bacteria produce human insulin

and then what're going to do is we're

going to take the insulin out of the

bacteria there's a special technique

where we can isolate that protein so now

we've got the human insulin and we can

bottle this up and we can use it to

treat diabetics who need uh doses of

insulin and that in a nutshell is how to

do genetic engineering keep in mind

though that this is only one example we

can move genes from different organisms

uh into other organisms so one

application is to make pesticide

resistant plants these have a gene from

uh bacteria that allows them produce

their own pesticide we can make bacteria

that can clean up toxic waste uh we can

produce proteins to dissolve blood clots

uh we can make growth hormone we can

even make acid washed genes and in class

we'll take a look at some other

applications of genetic engineering