The California Institute of Technology has developed ultrasound imaging systems that enable people to see gene expression for themselves.

Today, the latest issue of Science magazine reports a noteworthy paper.
a team at the California Institute of Technology developed a new ultrasound imaging system.
it can be in living animals, allowing scientists to see the expression of genes for themselves.
although the technology is still relatively preliminary, it is conceivable that once it matures, it will be able to lead to a breakthrough in the detection of a variety of diseases.
fact, scientists in the past have developed many ways to detect gene expression.
the most well-known of these, perhaps the green fluorescent protein (GFP) system.
this system can be under a microscope, allowing us to see which cells in the tissue have specific gene expression, and even allow us to see where the protein is in one cell.
, scientists who developed the system also shared the Nobel Prize in Chemistry in 2008.
but the GFP system also has a big limitation, that is, "light".
in a petri dish, light can trigger green fluorescence through thin layers of cells.
But it's easy to move the system into large live animals - their organs and tissues are too thick to penetrate.
What is the way to observe gene expression in large live animals in real time? The scientists' choice is "ultrasound imaging".
is no stranger to ultrasound imaging.
doctors use this very mature technique when examining heart defects or the development of a fetus.
its advantage is its ability to penetrate thick organs and tissues.
the next question, which is how to see specific cells with ultrasound.
scientists have taken inspiration from aquatic microbes that form a special protein structure in the body that resembles a balloon and fills with air in the middle.
this protein structure provides them with buoyancy for aquatic microorganisms.
in the eyes of scientists, the protein structure is sufficient to provide the resolution required for ultrasound imaging, given the difference in nature between the air in the structure and the moisture in the cells.
next, they have a technical dilemma to solve -- how to get these hollow protein structures into mammalian cells.
this is not a simple question.
the microbes that express these protein structures belong to pronuclear organisms, while mammals are eyress, and the genetic regulation of the two is very different.
, the protein structure requires the involvement of many different genes, which are also not simple to move to mammalian cells at the same time.
with the help of synthetic biology techniques, the team finally transferred the required genes into mammalian cell lines and allowed them to express them steadily.
kung fu is not responsible for people.
tested, these cells were finally able to form similar hollow protein structures.
next, to test whether these structures can actually aid ultrasound imaging.
the researchers did a set of controls: in one part of the cancer cells, they introduced this hollow protein structure; in another, they used a traditional fluorescent protein.
, the cancer cells were then injected to the left and right sides of the mice, respectively, to induce tumor spawning.
after a few days of induced expression, the researchers clearly saw the difference between the two systems.
limited to the permeability of the tissue, in the "fluorescent protein" group, we can only see "one" fluorescence, can not see too many details.
in the "hollow protein structure" group, ultrasound imaging clearly showed that only the outermost layer of the tumor had the expression of the reported gene.
follow-up histological tests, the accuracy of ultrasound imaging has also been confirmed.
can imagine that if the system can be followed up with application and development, we can better research and explore gene expression in living animals.
that's why so many scientists have shown a lot of interest in it.
"it can lead to new ways of observing gene regulation," said one scientist who was not involved in the study.
other scientists point out that the system has high requirements for gene editing.
want it to be used more widely, we need to lower the threshold for use further.
Source: Academic Latitude.