Distribution of Dileptus anser (Ciliata, Holotricha, Gymnostomatida) of various genotypes for mat locus in the concentration gradient of their gamones

When placed into the agar-chamber depression with concentration gradient of a heterologous (i.e., released by cells of a complementary mating type) gamone, ciliates accumulate within the zone of its highest concentration. The response was used to assay the kind of gamones excreted by ciliates of various mating types (MTs). It was shown preliminarily that two different gamones mixed even in the ratio 16:1 might be detected in the mixture by means of the bioassay. Ciliates of each of the three MTs, when homozygous in mat locus, release a specific kind of gamone(s). As to the mat heterozygotes, their gamone induces aggregation of only one of the two corresponding homozygotes. It is assumed, therefore, that a heterozygote excretes only one kind of gamone(s) similar to that of a homozygote with the same MT.