Identification and manipulation of male fertility genes in hexaploid bread
wheat is important for understanding pollen development and to gain novel
sources of nuclear genetic male sterility (NGMS). The maize Male sterile 45
(Ms45) gene has been shown to be required for male fertility. To investigate
the role of Ms45 gene in wheat, the team of Manjit Singh from DuPont Pioneer
induced mutations in the A, B and D homeologs of Ms45 using CRISPR-Cas9.
Several lines with various combinations of mutations were recovered,
including lines with mutations in all three homeologs. Analysis of these
mutants revealed that all three wheat Ms45 homeologs contribute to male
fertility and that the triple mutants are required to abort pollen
development and achieve male sterility. Furthermore, a wildtype copy of Ms45
gene from rice was able to restore fertility to these wheat mutant plants.
These results provide evidence on the function of MS45 function in wheat.
The Ms45 gene can potentially be used for a Seed Production Technology
(SPT)-like hybrid seed production system in wheat.