FURTHER EVIDENCE FOR A POSITIVE ROLE OF ACROSOME IN THE UPTAKE OF LABELLED AMINO ACIDS BY BOVINE AND AVIAN SPERMATOZOA

Abstract

Summary. Storage of an aqueous suspension of bull or buffalo spermatozoa at 0° C, followed by rewarming to room temperature, was found to result in a loss of the acrosome; this treatment was earlier shown to result in a release of labelled proteins from bovine spermatozoa which had been incubated with radioactive amino acids. Treatment with methanol of a suspension of bull or buffalo spermatozoa which had been incubated with radioactive amino acids, also resulted in a release of the labelled proteins and in disintegration or modification of the acrosome. This observation is discussed in relation to the previously reported autoradiographic studies on bull spermatozoa that had been incubated with 14C-labelled amino acids. In cock spermatozoa, which were earlier shown not to incorporate radioactive amino acids into their proteins, the acrosome appears to be present in a strongly modified form with properties different from those that characterize mammalian spermatozoa. It is concluded that mammalian spermatozoa can incorporate labelled amino acids specifically into the proteins of the acrosomal region.