The changes in lectin activity during the development of embryonic chick skin.

Changes in lectin activity during development of embryonic chick skin were studied. In the dorsal skin of the chick embryo in which feathers were formed, lectin activity first increased, during the period of dermal condensation, and then it decreased during the development of feathers. A similar change in lectin activity was also found in the anterior shank skin, the prospective scale region of the chick embryo. The embryonic cornea, in which no mesenchymal condensation took place, had lectin activity and did not show any developmental changes in lectin activity. Apteria regions of the dorsal skin, experimentally formed by treatment with hydrocortisone, gave low lectin activity. The lectin found in the embryonic skin showed specificity for lactose. The relationship found between lectin activity and dermal condensation in the embryonic chick skin is discussed.