Science news - cell biology

SNARE proteins. Nia Bryant


Please mouseover hard words to see what they meanBlue skies and annoying scientists

“All scientists are a bit annoying,” says Nia Bryant. “It's because we want to understand how everything works. I was always interested in how stuff works. I can’t remember not being like that. I think I annoy my lab, my family - even myself sometimes.”

The "stuff" she is interested in nowadays is cells - the tiny factories our bodies are made of, as well as the bodies of all animals and plants. Her research has both a pure and an applied side - although there is some overlap, she says.

In the lab

"It's all about what happens inside a cell. The basic question we're trying to answer is this: how does the cell organise itself internally?

"Cells in animals and plants are divided into compartments called organelles. So we're looking at how the cell determines the make-up of those organelles. This is important for many processes in the body – from producing hormones, such as insulin and adrenalin, to brain function and the firing of neurons.”

Figuring all this out with experiments on mammal cells would be difficult, costly and time-consuming. It could also bring up questions of ethics. So Dr Bryant and her group are working instead with yeast. They are using yeast as a model organism. Nia Bryant

Same but different

Yeast cells are quite similar to our own. Even though the last common ancestor of yeast and humans lived perhaps a billion years ago, there are a whole lot of similarities. Dr Bryant's group did a study last year, for instance, in which they took a yeast cell and removed one of its genes. "So you can see a defect - the cell is messed up in some way," she says.

The gene they deleted carried the code to make a particular protein in the yeast cell. "We then expressed the corresponding protein from a mouse cell in those yeast cells," says Dr Bryant. "It corrected the problem.

"What that shows is that the two protein molecules – one in yeast and the other in the mammal – are interchangeable. They are performing the same function.”

Pure and applied

Of the two streams to the research done by Dr Bryant's group, one is looking at how a particular family of proteins controls the way material is moved between organelles, she says. "They are called the SNARE family of proteins.“

The more applied side of the research is studying a molecule called Glut4. This is produced inside cells and has an important job to do in the body. It helps to clear glucose from the bloodstream. There are many steps to how it does this. Some are understood better than others.

If we look at the main steps, what happens is this. When the blood is carrying high levels of glucose (after a meal, for instance) the pancreas detects this and secretes insulin. This is then carried in the blood and sticks to the outside of the body's muscle and fat cells. That sends a signal to the inside of the cell.

Glut4 then moves from inside the cell out to the cell membrane. Once there, it opens little channels that let glucose molecules pass through, out of the blood and into the cell - which is where the body wants them to be.

Crossing the streamsThe control of SNARE complex formation and function. Nia Bryant

The pure and applied streams of research cross, says Dr Bryant."Because that movement of Glut4 from inside the cell is controlled by SNARE proteins. So we use findings from the pure science in the applied science side – which is nice for people to see possible applications for their work.”

Treatment of diabetes is a long-term goal of the work, she says. “If we can understand the movement of Glut4 in a healthy cell, it should give us insight into what is perturbed in a disease, such as diabetes.”

It would be an important discovery. But the prospect of making it is not what motivates Dr Bryant most. “My favourite thing in science is finding out something nobody ever knew before.

It happens often enough to drive you, but not so often you become blasé."

Blue skies research

Like most scientists Dr Bryant finds it difficult to work only at certain times of the day, she says. “I do long-distance running, which is fantastic thinking time. Ideas come out of nowhere. There are many aspects to our job – research, teaching, admin – and it can get very jumbled. Running clears your head. I’m a great believer in blue skies research, because you never know where applicability will come from.

“Building up knowledge is vital. The more we know, the more we’ll be able to fix. But we don’t know in advance which knowledge will help us fix which problem.”

More help with words

applicationcellcomplex conception DNA experiments
fertilisation genes gland inherit membrane molecule
organ pancreas proteinprotoplasm structures tissue

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