["Extracyclic" DNA synthesis and the accumulation of total protein and hemoglobin in erythroid series cells in anemia in pigeons].

Two types of biosynthetic processes associated with cytodifferentiation underlie the "reserve" erythropoiesis of pigeons during anemia: 1) cells rapidly increase their nuclear DNA amount up to the level of 4c, whereas the total protein remains at the initial level; furtheron, cells double also their protein amount, and then enter into the phase of differentiation and specialization; after having hemoglobin accumulation they divide; 2) a limited increase of DNA amount takes place up to the level not exceeding 130% of the initial level; in this case a synchronous increase of the hemoglobin amount is detected in the cell. The first type processes provide the accumulation of the specific product and the accelerated increase of the number of erythrocytes in the population. The second way is aimed only to the accumulation of the specific product in a greater amount.