Dr. Tan Xiaojun's Nature Article: How Cells Repair the "Recycling System" Related to Longevity

Researchers at the University of Pittsburgh have described for the first time the pathway by which cells repair damaged lysosomes, structures

"Lysosomal damage is a marker of aging and many diseases, especially neurodegenerative diseases such as Alzheimer's," said article author Jay Xiaojun Tan, Ph.

As a recycling system for cells, lysosomals contain powerful digestive enzymes that degrade molecular waste

First, the researchers experimentally destroyed lysosomes in lab-cultured cells and then measured the proteins

"PtdIns4P is like a red flag

Tan explains that ORP proteins work like rope

"The endoplasmic reticulum wraps around the lysosomes like a blanket, and normally, the endoplasmic reticulum and the lysosomes are almost non-contact, but once the lysosomes are damaged, we find that they hug each other

With this binding, cholesterol and a lipid called phosphatidylserine are transported to the lysosomes, helping to patch holes in membrane fences

"The beauty of this system is that all the components of the PITT pathway are known to be present, but they interact in this sequence or are not aware

The researchers speculate that in healthy people, small cracks in the membrane of lysosomal bodies are rapidly repaired

When Tan deleted the gene for the first enzyme PI4K2A in the encoding pathway, he found a sharp increase in tau fibryel diffusion, suggesting that defects in the PIT pathway could lead to the progression

The study was supported

essay

A phosphoinositide signaling pathway mediates rapid lysosomal repair