Single-nucleotide substitution determines pollen production in Japanese cedar

Abstract

Pollinosis, also known as pollen allergy or hay fever, is a global problem caused by pollen produced by various plant species1-6. 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 decades7. The MS4 (MALE STERILITY 4) 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 TKPR1 (TETRAKETIDE -PYRONE REDUCTASE) gene in this region. Transformation experiments using Arabidopsis thaliana showed that single-nucleotide substitution of CjTKPR1 determines pollen production. Broad conservation of TKPR1 beyond plant division could lead to the creation of pollen-free plant not only for Japanese cedar but also for broader plant species.