| Abstract: | Synthesis of the acid-soluble proteins in the early cleavage stage of the sea urichin, Hemicentrotus pulcherrimus, was investigated. As detected by the incorporation of lysine, the acid-soluble proteins were synthesized periodically even before the first cleavage, differing from the pattern of incorporation of tryptophan into the fraction. Cyclic synthesis occurred almost in parallel with DNA synthesis. However, the phase and periodicity of cyclic synthesis of the acid-soluble protein fraction were quite different from those found in the hot TCA-insoluble (acid-insoluble) protein fraction. The acid-soluble proteins were adsorbed on cation exchange resin, Amberlite CG-50, and gave an elution profile similar to that found for calf thymus histones. The migration pattern of these proteins on acrylamide gel also resembled that of histones. |
