Scientists in the US and UK have made a leap towards understanding how cells and their components communicate and behave.
A new generation of experiments using the power of new molecular techniques is enabling researchers to unravel the mechanisms that underlie complex behaviour.
“We are trying to understand the mechanisms behind how the human body works, so we can develop treatments to help treat disease, but we need to know the biological mechanisms of how that happens,” says Dr Chris Pyle, a microbiologist at the University of Southampton in the UK.
This new understanding of how cells work, and what happens to them when they communicate, could help with understanding how our body works and what we can do to help.
The basic idea is that when cells communicate with each other, they can use different strategies to get information from one another.
Dr Pyle and colleagues have used a technique called RNA-seq to sequence the genomes of human and mouse cells, and identified genes involved in cell communication.
The work was published online today in the journal Nature.
RNA-seq works by inserting DNA sequences into a sample of RNA, which can then be read using a genetic sequencer.
Once the DNA sequence has been identified, the researchers can sequence it in a large number of cells and then look for differences between the sequences.
They then look at the differences between different RNA molecules and how they interact to form what are called “transcripts”.
“These transcripts show us what kind of chemical messages are being sent by the cells,” says Pyle.
When they analyse the transcripts of the human cells, they see that the human genes are mostly involved in protein synthesis.
One of the genes, called p34, is involved in the protein synthesis of a protein called proteasome, which is the enzyme that turns proteins into their more complex and active forms.
The researchers also found that p34 is involved not only in proteasomal protein synthesis, but also in other cellular functions such as energy metabolism and cell migration.
Another gene, called P7, is part of the cell’s immune system, which helps protect the body from invading foreign cells and viruses.
This gene, too, plays a role in cell migration and cell survival, although researchers are not sure how it functions.
P7 is also found in a number of other animals, and is associated with immune responses in humans, including those caused by viruses and bacteria.
Scientists have long suspected that p30 and p34 could be involved in signalling between cells, but until now they had not found specific proteins that they could target.
So, Dr Pyle’s team turned to RNA-sequencing to investigate what genes were involved in these signalling.
They identified a protein known as p300, which has been associated with the signalling of proteins involved in immune responses.
While other researchers had identified some of the proteins involved, none of them matched up with p300.
“When we were working with these proteins, we realised we had missed something crucial,” says lead author Dr Robert Macleod from the University at Southampton.
“The proteins that were actually being involved were the ones that had the strongest interactions with p30.”
Using this new knowledge, Dr Macleods team used RNA-Seq to identify more than 400 genes associated with p3000.
By combining the information from the other researchers’ work, Dr Mcleod and his colleagues were able to identify about 60 proteins, most of which are involved in a wide range of functions.
One of these proteins was called p36.
“P36 plays a key role in the signalling that is required for the cell to move,” says Macleodes.
In addition, the team found that the proteins that make up the cell membrane are also involved in signaling between cells.
Together, the findings suggest that p36 is involved both in the cell communication and in the membrane organisation.
The findings also have implications for the understanding of the genetic basis of disease.
These new findings could lead to a new way of studying cell signalling, says Dr Maclod.
“We could potentially be able to make a genetic test that could detect changes in the levels of genes in cells that are affected by disease,” he says.
But this is just one example of the possibilities that arise from using RNA-Sequencing techniques.
“In the future, we are going to be able for the first time to study genes directly in cells, as opposed to looking at them in tissues,” says Mcleods co-author Dr John Roeser.
“This could have a huge impact on the way we understand how the body works.
Understanding how the molecular machinery of the body operates will be of great interest to the pharmaceutical and biotechnology industries.”
Dr Roesers group at Southampton has been studying the molecular basis of ageing for more than 30 years.
He says that the next stage of the work