Contents

05 December 2008
Vol 322, Issue 5907

About The Cover

Cover image expansion

COVER A mouse embryo at 9 days of gestation, stained for α-fetoprotein in the liver bud and yolk sac (upper left and right green domains) and for the transcription factor Pdx-1 in the ventral and dorsal pancreas buds (upper and lower red domains). Understanding the basis for organ development can provide insights into disease and stem cell programming. See the special section beginning on page 1489 . Image: Ewa Wandzioch and Ken Zaret