How Cells Resist the Pressure of the Deep Sea

“They are looking into an country that, to a ample degree, has not been explored,” said Sol Gruner, who researches molecular biophysics astatine Cornell University; helium was consulted for the survey but was not a co-author.

Plasmalogen lipids are besides recovered successful the quality brain, and their relation successful deep-sea membranes could assistance explicate aspects of compartment signaling. More immediately, the probe unveils a caller mode that beingness has adapted to the astir utmost conditions of the heavy ocean.

Insane successful the Membrane

The cells of each beingness connected Earth are encircled by fatty molecules known arsenic lipids. If you enactment immoderate lipids successful a trial conduit and adhd water, they automatically enactment themselves up backmost to back: The lipids’ greasy, water-hating tails commingle to signifier an interior layer, and their water-loving heads put unneurotic to signifier the outer portions of a bladed membrane. “It’s conscionable similar lipid and h2o separating successful a dish,” Winnikoff said. “It’s cosmopolitan to lipids, and it’s what makes them work.”

For a cell, an outer lipid membrane serves arsenic a carnal obstruction that, similar the outer partition of a house, provides operation and keeps a cell’s insides in. But the obstruction can’t beryllium excessively solid: It’s studded with proteins, which request immoderate wiggle country to transportation retired their assorted cellular jobs, specified arsenic ferrying molecules crossed the membrane. And sometimes a compartment membrane pinches disconnected to merchandise chemicals into the situation and past fuses backmost unneurotic again.

For a membrane to beryllium steadfast and functional, it indispensable truthful beryllium sturdy, fluid, and dynamic astatine the aforesaid time. “The membranes are balancing close connected the borderline of stability,” Winnikoff said. “Even though it has this truly well-defined structure, each the idiosyncratic molecules that marque up the sheets connected either side—they’re flowing astir each different each the time. It’s really a liquid crystal.”

One of the emergent properties of this structure, helium said, is that the mediate of the membrane is highly delicate to some somesthesia and pressure—much much truthful than different biologic molecules specified arsenic proteins, DNA oregon RNA. If you chill down a lipid membrane, for example, the molecules determination much slowly, “and past yet they’ll conscionable fastener together,” Winnikoff said, arsenic erstwhile you enactment olive lipid successful the fridge. “Biologically, that’s mostly a atrocious thing.” Metabolic processes halt; the membrane tin adjacent ace and leak its contents.

To debar this, galore cold-adapted animals person membranes composed of a blend of lipid molecules with somewhat antithetic structures to support the liquid crystal flowing, adjacent astatine debased temperatures. Because precocious unit besides slows a membrane’s flow, galore biologists assumed that deep-sea membranes were built the aforesaid way.