The foot bone’s connected to the leg bone, the leg bone’s connected to the knee bone — thanks in part to a newly discovered chemical bond, researchers report in the Sept. 4 Science. The bond — never before seen in living things — was found buried in the basement membrane, a tough, structural layer of cells that surrounds most tissues. A greater understanding of the links within this membrane may lead to new approaches for targeting tumors and for treating a number of diseases.
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Animals from roundworms to humans have basement membranes, and the layer has long been recognized as important for a body’s structural integrity. The membranes surround tissues, tethering muscle to skin or to cartilage, and in the kidney’s case, act as a huge filter for blood. Basement membranes also play a signaling role, acting sort of like a cellular thermostat.
“If the basement membrane misbehaves, then the cell misbehaves,” comments Raghu Kalluri, chief of the matrix biology division at Harvard Medical School in Boston.