Figure 6.

pCRY influences the transcript accumulation of the gamete-specific gene GAS28 under blue light illumination during gametogenesis, mating ability, and its maintenance as well as the germination efficiency. Asterisks indicate significant differences estimated by Student’s t test (*, P < 0.05; **, P < 0.01; and ***, P < 0.001; n.s., nonsignificant). A, pCRY transcript levels in pregametes (PG) and gametes (G). Transcript accumulation was quantified by RT-qPCR for the wild type (WT), pcry mutant (pcry_mut), and complemented mutant (compl_SAG). Cells were grown under an LD12:12 cycle, then transferred to TAP medium without nitrogen at the end of the light phase and kept in darkness for 14 h. Afterward, the cells were illuminated with blue light for 5 h to convert PG to G. LEDs with an energy fluence rate of 2.6 W m⁻² were used. Total RNA was isolated, and equal amounts of RNA were used for RT-qPCR with RACK1 as a reference gene. Changes in the transcript levels after blue light illumination (G) in comparison with dark-adapted cells (PG) are shown (n = 3 biological replicates; error bars represent sd). B, Germination of zygospores in percentage after 10 d. Crossings of mating type plus (mt⁺) and minus (mt⁻) of different combinations are shown: WT, wild-type strain; pcry_mut, pcry mutant strain; pcry_compl, complemented strain of the pcry mutant (mt⁺). The germination of zygospores (see “Materials and Methods”) of wild-type strains CC-124/mt⁻ (WT⁻) and CC-125/mt⁺ (WT⁺) is shown as a homozygote (WT⁺ × WT⁻) as well as the heterozygotes (WT⁺ × pcry_mut⁻ and pcry_mut⁺ × WT⁻) and the homozygote of pcry mutant strains with mt⁺ and mt⁻ (pcry_mut⁺ × pcry_mut⁻). In addition, the heterozygote of a complemented strain/mt⁺ (see “Materials and Methods”; Supplemental Fig. S8) and a wild-type CC-124/mt⁻ (pcry_compl⁺ × WT⁻) is shown. C, Mating ability of the wild type, pcry_mut, and the complemented strain pcry_compl. For the test, PG kept in the dark as well as PG illuminated for 1 h with light (G1) were used (see “Materials and Methods”). The mating ability of G1 of the wild type was set to 100% and used for comparison. D, Mating ability after dark treatment of the wild type, pcry_mut, and pcry_compl. G1 gametes were put in the dark for 1 h to deactivate the mating ability. The gamete formation rate of G1 gametes of each strain was set to 100% separately.