INTRODUCTION—We live in the golden age of genetics, but the fundamental unit of biology is still arguably the cell. The scientists gathering next week in Denver for the American Society for Cell Biology's annual meeting need little reminding of that, but as they detail their latest insights and data, it's useful to reflect on how much of the cell remains unexplained or unknown.

News Focus


Science highlights five enduring mysteries of cell biology.

Do Lipid Rafts Exist?

Many scientists argue that the molecular platforms that sail on the cell's outer membrane, known as lipid rafts, either don't exist or have no biological relevance, but their supporters insist the idea remains afloat.

How Does a Cell Know Its Size?

Researchers have finally begun to identify potential size-sensing mechanisms within cells, but they admit there's still a lot to learn.

How Does the Cell Position Its Proteins?

Somehow, a cell must get all its proteins to their correct destinations-and keep these molecules out of the wrong places. The mystery of how cells place their protein repertoire is far from solved.

How Do Hungry Cells Start Eating Themselves?

Cell biologists might be close to learning where the internal membrane comes from that a hungry cell sprouts to encapsulate some of its contents and break them down for reuse.

Does a Gene's Location in the Nucleus Matter?

How the pattern of chromosomes and subnuclear bodies in the cell nucleus affects gene activity and other cellular functions is an enduring mystery in biology, one that won't be unraveled soon.

Cell Biology's Open Cases

A few more mysteries that could keep cell biologists working long hours.


The Unfolded Protein Response: From Stress Pathway to Homeostatic Regulation

Cells respond when protein folding in the endoplasmic reticulum is disrupted.

Road to Ruin: Targeting Proteins for Degradation in the Endoplasmic Reticulum

The cell monitors the folding of membrane and secretory proteins and disposes of those that are misfolded.
Science Talk

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Science Podcast
Science Podcast
Science deputy news editor John Travis describes some of the biggest mysteries facing cell biologists today.
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