“Under a microscope, it’s hard to miss. Take just about any cell, find the nucleus, then look inside it for a dark, little blob. That’s the nucleolus. If the cell were an eyeball, you’d be looking at its pupil.
You’ve got one in every nucleus of every cell in your body, too. All animals do. So do plants, and yeast — and anything with a cell with a nucleus. And they’ve become much more important in our understanding of how cells work. […]
You may have forgotten this from biology class, but the nucleolus is the cell’s ribosome factory. Ribosomes are like micro-machines that make proteins that cells then use for purposes like building walls, forming hairs, making memories, communicating and starting, stopping and slowing down reactions that help a cell stay functioning. It uses about 80 percent of a cell’s energy for this work. […]
If building a cell were like building a building, and the DNA contained the blueprint, the nucleolus would be the construction manager or engineer. “It knows the supply chain, coordinates all the jobs of building, does quality control checks and makes sure things continue to work well,” said Dr. Antebi. […]
Researchers have found that modest dietary restriction and exercise shrank nucleoli in muscle cells of some people over age 60. People with diseases like cancer or progeria, a kind of accelerated aging, tend have enlarged nucleoli.
You can see these kinds of effects in many different species. “It’s amazing — even if genetically identical, some live a short life and some live a long life,” said Dr. Antebi. […]
“We think that the smaller nucleoli may be a cellular hallmark of longevity” in certain cells under certain conditions, he added.”