eukaryotes – Quanta Magazine

The Mystery of the Missing Multicellular Prokaryotes

Veronique Greenwood — Thu, 02 May 2024 14:23:48 +0000

Every organism visible to the naked eye is a mass of genetically identical cells. Each of these multicellular creatures started as a single cell that divided countless times to produce its body. And while each cell contains the same genome, they express their DNA in a variety of ways, giving rise to specialized cells and tissues that perform different roles, such as skin, liver or immune cells.

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Cellular Self-Destruction May Be Ancient. But Why?

Veronique Greenwood — Wed, 06 Mar 2024 14:54:31 +0000

It can be hard to tell, at first, when a cell is on the verge of self-destruction. It appears to be going about its usual business, transcribing genes and making proteins. The powerhouse organelles called mitochondria are dutifully churning out energy. But then a mitochondrion receives a signal, and its typically placid proteins join forces to form a death machine. They slice through the cell with...

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A ‘Lobby’ Where a Molecule Mob Tells Genes What to Do

Philip Ball — Wed, 14 Feb 2024 15:47:52 +0000

The discovery during the Human Genome Project in the early 2000s that we humans have only about 20,000 protein-coding genes — about as many as the tiny soil-dwelling nematode worm, and less than half as many as the rice plant — came as a shock. That blow to our pride was softened, though, by the idea that the human genome is rich in regulatory connections. Our genes interact in a dense network...

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Fossilized Molecules Reveal a Lost World of Ancient Life

Yasemin Saplakoglu — Mon, 23 Oct 2023 14:11:26 +0000

A tree has something in common with the weeds and mushrooms growing around its roots, the squirrels scurrying up its trunk, the birds perched on its branches, and the photographer taking pictures of the scene. They all have genomes and cellular machinery neatly packed into membrane-bound compartments, an organizational system that places them in an immensely successful group of life forms called...

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Primitive Asgard Cells Show Life on the Brink of Complexity

Joshua Sokol — Tue, 11 Apr 2023 14:22:43 +0000

An oak tree. The symbiotic fungus intertwined with its roots. A cardinal chirping from one of its branches. Our best clue yet to their shared ancestor might have arrived in electron microscope images that were unveiled in December. “Look!” said the microbiologist Christa Schleper, beaming as she held a printed, high-resolution image in front of her webcam at the University of Vienna.

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