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This year marks the thirtieth anniversary since embryonic stem (ES) cells were first isolated from mouse blastocysts. In this Timeline, one of the scientists to isolate mouse ES cells in 1981 gives a personal account of the ideas that led to, and followed, this milestone.
This timeline article pays tribute to the late James Fred 'Paulo' Dice, whose vision of selective protein degradation in lysosomes led to the discovery of chaperone-mediated autophagy.
In 1971, Günter Blobel and David Sabatini formulated the signal hypothesis, which proposed that proteins contain signal sequences that target them for secretion. Over the past 40 years this concept has expanded, and topogenic signals are now known to target proteins to many parts of the cell.
