A single-nucleotide substitution of CjTKPR1 determines pollen production in the gymnosperm plant Cryptomeria japonica

Abstract

Pollinosis, also known as pollen allergy or hay fever, is a global problem caused by pollen produced by various plant species. The wind-pollinated Japanese cedar (Cryptomeria japonica) is the largest contributor to severe pollinosis in Japan, where increasing proportions of people have been affected in recent decades. The MALE STERILITY 4 (MS4) locus of Japanese cedar controls pollen production, and its homozygous mutants (ms4/ms4) show abnormal pollen development after the tetrad stage and produce no mature pollen. In this study, we narrowed down the MS4 locus by fine mapping in Japanese cedar and found TETRAKETIDE α-PYRONE REDUCTASE 1 (TKPR1) gene in this region. Transformation experiments using Arabidopsis thaliana showed that single-nucleotide substitution (“T” to “C” at 244-nt position) of CjTKPR1 determines pollen production. Broad conservation of TKPR1 beyond plant division could lead to the creation of pollen-free plants not only for Japanese cedar but also for broader plant species.

GhTKPR1_8 functions to inhibit anther dehiscence and reduce pollen viability in cotton

“…A maize double mutant, zmtkpr1 _ 1 / zmtkpr1 _ 2 , exhibited absolute male sterility, accompanied by delayed tapetal degradation, a defective exine, and abnormal anther cuticles (An et al, 2024). The tkpr1 mutant of Cryptomeria japonica displayed a thinner pollen wall compared to the wild type, reduced pollen grain count, and the production of non‐viable pollen (Kakui et al, 2023). GTKPR1 ‐RNAi lines in Gerbera had severely distorted pollen grains with damaged exine and complete loss of viability (Zhu et al, 2008).…”