In recent years, we’ve seen a lot of new discoveries in the healthcare and medical industry.
In 2006, a major breakthrough was made, when scientists realized the possibility to reprogram cells. This led to the discovery of the Yamanaka factors, and researchers are continuing to investigate how they can be used in cellular reprogramming.
In this post, we are going to explore Yamanaka factors, look at what they are, and how they are involved in cellular programming. We’ll also assess some of the latest breakthroughs and discoveries that have been made in regards to these factors.
What Are Yamanaka Factors?
Let’s first consider what Yamanaka factors are. Now, to better understand this, we need to talk about differentiation of cells. There are differentiated and undifferentiated cells.
Undifferentiated cells generally consist of stem cells.
Think of them as a brand new flash drive that you’ve just bought. There’s nothing on it - it’s essentially a “clean slate”. These cells differentiate to become specific cells. Examples include heart cells, muscle cells, and brain cells.
This is also where Yamanaka factors come into the picture. See, these factors are actually specific programs that have the capability to reprogram cells. What they essentially do is turn adult cells in the body into what is known as pluripotent stem cells [1].
Once this happens, the pluripotent stem cells become undifferentiated once again. Then, these cells essentially have the ability to become differentiated - allowing them to repopulate areas of the body where the cell count runs low.
As for the more recent research into the Yamanaka factors and cellular programming in general, scientists are turning their focus to the techniques they can use to take advantage of the discovery in modern day medicine.
For example, there is a lot of interest in using pluripotent stem cells, also known as iPS cells, in disease modeling and even cellular therapy. Plus, many researchers have shown an interest in the use of iPS cells to assist with drug discovery.
There are four specific Yamanaka factors that have been identified, each of them being a specific protein. These proteins work at a cellular level, combined, to promote things like the growth and survival of cells all over your body.
Cellular Programming
Cellular programming is a topic that meets a lot of controversy. Yet, it still holds a lot of promise when it comes to treating diseases, finding new ways to create drugs, and several other areas of medicine.
The term cellular programming actually refers to certain methods that are used to make changes to how cells behave. The principle behind this stems from the fact that genes are expressed in every cell within our bodies.
So, with cellular programming or reprogramming, the expression of genes are essentially modified. And when this is done, it creates an opportunity to change certain things related to the cell and how it functions.
There are a couple of different methods that scientists are investigating in terms of cellular programming. Plus, these methods can be used in different applications, which we’ll take a closer look at in this section.
Applications Of Cellular Programming
There are different areas in healthcare and medicine where cellular programming showcases a lot of potential.
Understanding where and how it can be used can help you get a better picture of where these techniques might fit into our lives, right now and in the future.
Let’s take a closer look at some potential applications of cellular programming that are being actively studied and even, in some cases, already used.
Drug Development
One of the most promising areas of cellular programming research lies in drug development. Pharmaceutical drugs play a crucial role in the treatment of various diseases.
In cases of both chronic and acute conditions, medication can help to reduce the impact of the disease and lessen the burden of the symptoms. Some drugs can also effectively reduce the rate at which conditions progress, essentially contributing to the lifespan of the individual.
Researchers can use cellular programming in order to program cells. The idea here is to change certain gene expressions. New and experimental drugs can then be tested on these modified cells.
It is a highly effective method for testing the efficacy of a drug before considering human trials. This helps to reduce the hazards that people may face in a clinical trial when there is a lot of uncertainty regarding a new drug that is being tested.
Disease Modeling
Even though a lot of research goes into every disease known to mankind, there are still many things that scientists need to discover. But, there are often limitations to researching and understanding diseases when looking at patients.
This is another area where cellular programming can be useful. When cellular programming is used, it’s possible for scientists to create a model of a specific disease in a lab setting.
Once this model is created, the scientists behind the study can then look at how the disease develops, pathways it affects, and other elements that will help them gain more insight into the condition.
This also creates an opportunity to identify new ways to treat diseases. Through drug development, new pharmaceuticals can then be tested on the disease model to determine efficacy and potential safety concerns.
Cellular Therapy
In human subjects, it’s also possible to use cellular programming. This is called cell therapy and it can be used to help improve cellular function and survival in cases where the individual has a certain disease.
It’s possible to use cellular programming to create new cells that have the capability to repair organs, tissues, and other cells that have been damaged, for example.
This can lead to breakthroughs in the treatment of diseases that are not yet fully understood.
Cellular programming is an emerging field and there is continuous research on this topic. This means that while these are three common areas of how it is used right now, more applications for cellular programming might be discovered in the future.
Methods Of Cellular Programming
Apart from understanding what cellular programming can be used for, it’s also important to have knowledge about the methods that scientists are able to use. There are a couple of methods that have been identified to assist in programming cells.
Let’s take a closer look at these methods and how each of them works.
Transcriptional Factors: First up is transcriptional factors. It’s one of the more researchers areas that basically uses proteins that are able to bind themselves to specific sequences within your DNA.
When scientists use these transcriptional factors or proteins, they have the ability to turn certain genes on or off. For example, if a specific gene normally doesn’t turn on in a certain process, they can use this protein to rewrite the code and make it turn on.
This gives scientists the ability to use transcriptional proteins to make changes to the specific genes that are expressed in a cell that they are targeting.
Epigenetic Programming: Another method that is being studied for cellular reprogramming relates directly to your epigenetics. This is a field of study that focuses on how certain environmental factors affect your gene expression.
The idea here is to find ways to modify how your genes are expressed without actually making changes to your DNA. Essentially, scientists will adjust how your DNA is packaged.
In basic terms, the scientist may add or remove a methyl group to a specific area of your DNA sequence. This can affect things like how your histones behave and how certain genes are read and expressed.
Cellular Fusions: Scientists are also working on methods that would allow them to essentially fuse two cells together. What this does is it helps the scientists create “hybrid cells”.
These hybrid cells would then contain properties from each of the cells that were used to make the fusion. It can then be used to produce specific functions in the study subject.
Apart from these methods, researchers are also actively looking at methods that would allow them to transfer the genetic makeup of a somatic cell into an egg cell. In this particular case, the nucleus of a somatic cell that is taken from the body is added to a cell that doesn’t have a nucleus.
Understanding Yamanaka Factors
Now that we’ve covered the basics of Yamanaka factors and looked at cellular programming, let’s dive deeper into these specific factors.
In this section, we are going to take a closer look at how the Yamanaka factors were discovered and also consider the different types of factors.
We’ll also take a closer look at the role that Yamanaka factors play in cellular reprogramming.
The Discovery Of Yamanaka Factors
Over the last couple of years, we have seen a lot of new discoveries in the medical industry - and the Yamanaka factor is only one of them. This, however, is one of the more recent discoveries that was made in Japan.
The Yamanaka factors were discovered for the first time in 2006 [2]. It was Shinya Yamanaka who discovered them, hence the name “Yamanaka factors”. He and his team studied cellular programming and gene expression at Kyoto University.
At the time, they found that it was possible to use certain factors (proteins) in order to reprogram the adult cells from human subjects to become pluripotent stem cells (also known as iPSCs).
Types Of Yamanaka Factors
Now, an important thing to take into consideration is the fact that there are four different Yamanaka factors that were discovered. And these include Oct4, Sox2, Klf4, and c-Myc.
In this section, we are going to take a closer look at each of these types to give you a better idea of how every protein that is considered a Yamanaka factor works and what it does. This is a foundation when it comes to building up knowledge on cellular programming and these factors [3].
Oct4
The first Yamanaka factor is called Oct4. It’s actually a type of transcription factor that plays an incredibly important role in the pluripotency of embryonic stem cells.
This factor is expressed in iPSCs (which we covered before in this article) and essentially binds to a specific sequence of DNA. It then helps to activate certain genes that are involved with cellular growth and differentiation.
Sox2
Another transcription factor that’s part of these four proteins, known as Sox2. It’s also important for the embryonic stem cell pluripotency and, similar to Oct4, Sox2 is also expressed in iPSCs.
It’s another essential protein for cellular growth. Sox2 also contributes to the differentiation of cells in order to ensure specialized cells can be produced in your body. But, that’s not all, as Sox2 also helps to improve the pluripotency of your cells.
Klf4
Now, not all of the transcription factors are essential for cell health. And that’s where Klf4 comes in. It’s a non-essential transcription factor, but when it is active, it can still yield certain benefits.
See, Klf4, when activated, helps in maintaining the pluripotency of your stem cells. It’s another protein that has the capability to bind to your DNA sequences and affect which genes are going to be activated (or expressed).
c-Myc
This is a proto-oncogene that’s also not essential for the pluripotency and survival of cells, but stills can provide a number of potential advantages for cellular health.
c-Myc, similar to the other Yamanaka factors, binds to DNA. This allows it to make changes to which genes are going to be expressed.
One thing to keep in mind here, however, is that it seems like c-Myc does play a significant role in the reprogramming process where cells go from an adult cell to a stem cell.
Something important that we should also mention here is the fact that all four of these factors play an important role in the cellular reprogramming process. While each has their individual role to play, they also work together to make certain things possible.
Importance Of Yamanaka Factors In Cellular Reprogramming
There is a lot of interest in Yamanaka factors when it comes to reprogramming cells.This is because there are several ways in which Yamanka factors can be used to help scientists reprogram cells and potentially find new ways to treat diseases that they are struggling to address.
Now, one of the biggest departments that could benefit here would be regenerative medicine. These medicines generally focus on helping to restore and repair damaged tissues, cells, and even organs. It’s a subject that has already gained a lot of attention.
The four Yamanaka factors pose a potential target when developing new types of regenerative medicines.
It could help to pave the way to more effective approaches to repairing damaged cells - thus also helping to restore functionality of vital organs and bodily tissue.
Yamanaka factors in cellular reprogramming also serve as a foundation to help with drug discovery, as well as to create personalized medicine. For example, these methods hold the potential to allow scientists to create personalized tissues.
When these tissues are transplanted to the patient, it reduces the risk of tissue or organ rejection. In terms of drug discovery, Yamanaka factors can be used, alongside cellular reprogramming findings, to learn about new approaches to treating serious and chronic diseases.
The Four Yamanaka Factors
The four Yamanaka factors include Oct4, Sox2, Klf4, and c-Myc. They’re all incredibly important when it comes to reprogramming adult cells and reduces the need to use embryonic stem cells in this field of research.
The adult cell is reprogrammed into an induced pluripotent stem cell. And, in turn, this cell can then become a specialized cell.
Together, the four proteins bind to specific DNA sequences in order to initiate this reprogramming function .
When the proteins bind to these DNA sequences, it essentially acts as instructors, changing the way your genes are expressed (no, they do not change your genes, but only their expression).
The four Yamanaka proteins activate genes that have a role to play in three important functions of a cell: growth, differentiation, and pluripotency. Even though some of these proteins are not essential for cell pluripotency and growth, they still play important roles.
Cellular Reprogramming Techniques Using Yamanaka Factors
There are a couple of techniques that researchers have already developed in order to assist with cellular reprogramming - particularly in terms of using the Yamanaka factors.
To better understand the potential that these techniques pose, we’re going to break things down into the two most common ones that are being used and studied at the moment.
Each of these techniques holds a lot of promise, but there are a couple of important differences between them.
Induced Pluripotent Stem Cells (iPSCs)
A pluripotent stem cell is like a blank canvas. It can take on any shape or form. Well, in the human body, this is sometimes also referred to as an undifferentiated cell. It’s a type of cell that can become any cell that is present in the human body.
But, we’re born with a limited supply of stem cells. And this is an area where the Yamanaka factors come into play. Researchers have found that it’s possible to actually reprogram an adult cell and turn it into a pluripotent stem cell.
Now, in this particular case, we call these induced pluripotent stem cells - since certain techniques were used to actually induce the change in this cell.
In order to do this, four specific genes are used in the process. The cell that’s being converted into an iPSC are exposed to Oct4, Sox2, Klf4, and c-Myc. If you recall a previous section in this article, you should remember that these are actually the four Yamanaka factors.
Direct Lineage Conversion (DLC)
Direct lineage conversion is definitely a much newer technique when compared to iPSCs. It’s actually a technique that doesn’t use the Yamanaka factors, but rather focuses on a therapeutic approach called epigenetic reprogramming.
Epigenetics is the effects of the environment and other factors on how our genes are expressed. And DLC takes advantage of this factor - the fact that environmental elements can affect gene expression.
It’s not a technique that is going to actually make changes to your DNA. Instead, the technique changes how your histones package, increasing or decreasing availability of specific DNA sequences and genes.
Improving Cellular Reprogramming Using Yamanaka Factors
Cellular reprogramming is not a new study area in the healthcare industry and a lot of different discoveries have already been made.
With the discovery of Yamanaka factors, researchers now have new therapeutic models that they can turn to.
And through these factors, there are several ways in which cellular reprogramming can now be improved to a point where it becomes more effective, while also mitigating some of the risks that have been linked to other techniques that are used.
Let’s take a closer look at how these Yamanaka factors can assist in improving cellular reprogramming.
Transcriptional Activators
First up is transcriptional activators. Yamanaka factors include four specific proteins and some of them are actually transcriptional factors.
Now, by targeting these proteins and factors, researchers generally have an easier time achieving something specific.
For example, it becomes much easier to target a specific DNA sequence, adjust histone packaging, and ultimately affect gene expression when transcriptional factors and activators become the target for a therapy.
Small Molecules
The use of Yamanaka factors as a resolve for delivering drugs in the form of small molecules is another promising area in cellular reprogramming.
These factors can be targeted and used alongside tiny molecules that act as drugs. In turn, this creates a delivery method that ensures these small molecules are able to reach the specific proteins that they need to change.
It basically forms another foundation for reprogramming cells at an effective level without running into a significant number of risks.
Epigenetic Modifiers
We’ve covered epigenetics several times before in this article. And once more, it comes into the picture when looking at how Yamanaka factors can be used to improve the process of cellular reprogramming.
By targeting the Yamanaka factors, it’s possible to use these proteins as a way to make epigenetic modifications. These epigenetic modifications would then alter gene expression. It alters which genes are and aren’t expressed in a cell.
Ethical Considerations
It’s important to note that stem cell research and studies on cellular programming - these are all controversial topics. See, not everyone sees these research areas in the same perspective.
Some people believe that genes should not be modified, but these are often the ones who are against making “designer babies”. There are ethical researchers who are trying to make a real difference in treating disease.
Due to the fact that it’s a controversial topic, it’s really important to view things from both sides, be unbiased, and to take a few ethical considerations into account.
So, let’s take a closer look at the ethics related to stem cell research, cellular reprogramming, and similar research areas.
Stem Cell Research And Ethics
When it comes to stem cell research, many people believe that it is morally wrong to take embryonic stem cells from an embryo.
The main idea behind this thought is the fact that embryos are potential humans.
And when embryonic stem cells are removed from an embryo, it destroys the embryo in the process. Thus, this is something important that needs to be discussed and will continue to remain a question of whether or not it is morally wrong.
According to some, stem cell research and cellular reprogramming holds the potential to interfere with genetics and DNA, and even raises the possibility to create human clones. This could lead to a world of “designer babies’.
Some also believe that unethical use of these technologies could lead to the creation of slaves and soldiers, which is another moral factor that needs to be elaborated on further.
Plus, it’s also believed that the risk of creating new diseases through cellular programming is too great compared to the potential benefits that we might be able to obtain through these techniques.
Public Perception Of Cellular Reprogramming
The opinions among the public in terms of cellular reprogramming are mixed. One research study actually looked at how the public perceives stem cell research in 2018.
In this study [4], there were 2,212 American citizens who responded to a survey that the researchers sent out. The idea was to get a better understanding of how the general population perceives these research areas.
About two thirds of these people agreed or strongly agreed that stem cell research is important and more studies on these subjects should be conducted.
However, one third of the people did not agree. People of different religious and political views were included to ensure there was a great diversity in the responses that could be recorded in the survey.
Legal And Regulatory Considerations
There is also the legal landscape that needs to be considered when it comes to stem cell research and the use of things like the Yamanaka factors.
Here, we should note that the regulations and laws regarding these study subjects are not the same in every country. Thus, when you want to learn more about the legal status and specific regulations regarding stem cell research, you’ll first need to consider what country you want to focus on.
Some countries do not have any legal restrictions on stem cell research. With this said, however, there are still those ethical concerns that have to be taken into consideration by researchers and scientists .
Frequently Asked Questions
What are the natural Yamanaka factors?
There are four main natural Yamanaka factors that were discovered. These include Oct4, Sox2, Klf4, and c-Myc.
These are transcription factors that play a really important role in ensuring the pluripotency of embryonic stem cells. They also work together to help with cell growth and renewal.
What is the impact factor of cellular reprogramming?
Currently, the impact factor of cellular reprogramming is reported as 2.257 [5].
This is the latest data that have been published to date, with a Research Impact Score of 0.8 and a Citescore of 3.5. The impact factor of cellular reprogramming might change within the next one-year period.
How does Yamanaka factors reverse aging?
The four proteins that make up Yamanaka factors can essentially be used to reprogram normal adult cells into another type of cell.
These cells are undifferentiated and called pluripotent stem cells. They can then take up the form of different differentiated cells in your body.
How are Yamanaka factors expressed?
There are different ways in which Yamanak factors are expressed. This includes transcriptional regulation, post-translational modification, and epigenetic regulation.
These factors can affect how DNA is translated into RNA and how your genes are expressed.
Do stem cells increase lifespan?
It is sometimes possible for stem cells to increase lifespan, but more evidence is needed to provide a definite answer.
Right now, it’s known that stem cells might present a therapeutic option for age-related diseases, which could help to reduce premature mortality.
Why was Shinya Yamanaka discovery so important?
The discovery was a breakthrough since it showed how adult cells can be reprogrammed, essentially making them undifferentiated.
In turn, this technique could be used to help increase differentiated cells in areas where cellular senescence and death happens too quickly.
Conclusion
Yamanaka factors were first discovered in 2006 and since then, have received a lot of attention. They’re basically proteins that have the ability to reprogram your adult cells. When this happens, these adult cells become pluripotent stem cells.
There are still a lot of things that scientists need to discover about cellular reprogramming and the role of Yamanaka factors. Yet, there is already evidence that these factors can play a vital role in helping to reprogram cells.
This could help to improve the treatment of diseases that are currently difficult to manage. It could also give scientists an opportunity to discover new drugs and perhaps even slow down the rate at which we age.
References
- Yamanaka factors critically regulate the developmental signaling network in mouse embryonic stem cells. Retrieved from https://pubmed.ncbi.nlm.nih.gov/19030024/
- Advances in Pluripotent Stem Cells: History, Mechanisms, Technologies, and Applications. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6987053/
- Yamanaka Factors and Partial Cellular Reprogramming. Retrieved from https://www.lifespan.io/topic/yamanaka-factors/
- Center releases new public survey on stem cells. Retrieved from https://www.eurekalert.org/news-releases/829023
- Cellular Reprogramming. Retrieved from https://research.com/journal/cellular-reprogramming
