Traveling protein waves reveal how dividing cells set chromosome-splitting spindle size

When a human cell prepares to split into two daughter cells, it must first construct a tiny internal machine called the mitotic spindle—a structure of protein fibers that physically pulls chromosomes apart and deposits one set into each new cell.

Get the spindle the right size and the chromosomes segregate cleanly.

Getting it wrong could result in the chromosomal errors that fuel cancer. ...