Retinoic acid (RA) is a vitamin A-derived, non-peptidic, small lipophilic molecule that acts as
ligand for nuclear RA receptors (RARs), converting them from transcriptional repressors to …

Analyses of steroid receptors are important for understanding molecular details of
transcriptional control, as well as providing insight as to how an individual transacting factor …

The zone of polarizing activity (ZPA) is a region at the posterior margin of the limb bud that
induces mirrorimage duplications when grafted to the anterior of a second limb. We have …

Morphogens are long-range signaling molecules that pattern developing tissues in a
concentration-dependent manner. The graded activity of morphogens within tissues …

The histo-blood group ABO, the major human alloantigen system, involves three
carbohydrate antigens (ABH). A, B and AB individuals express glycosyltransferase activities …

Retinoids (vitamin A) are crucial for most forms of life. In chordates, they have important roles
in the developing nervous system and notochord and many other embryonic structures, as …

The bicoid (bcd) protein in a Drosophila embryo is derived from an anteriorly localized
mRNA and comes to be distributed in an exponential concentration gradient along the …

All-trans retinoic acid (RA) has previously been shown to modulate the transcriptional
properties of the retinoic acid receptor (RAR) and retinoid X receptor (RXR). The inability of …

The maternal gene bicoid (bcd) organizes anterior development in Drosophila. Its mRNA is
localized at the anterior tip of the oocyte and early embryo. Antibodies raised against bcd …

The reliable development of highly complex organisms is an intriguing and fascinating
problem. The genetic material is, as a rule, the same in each cell of an organism. How then …