09 November 1990
Vol 250, Issue 4982

About The Cover

Two functionally related jaw muscles in zebrafish specifically expres engrailed-homeoprotein in their nuclei. Expression begins in the muscle precursors and may be involved in determining their identities. Immunolabeled (stained nuclei) and unlabeled striated muscle fibers are shown on either side of associated jaw cartilage in a 3-week-old zebrafish. See page 802. [Polarized microphotograph by Kohei Hatta]