Transcriptome Comparison between Two Strains of Ustilago esculenta during the Mating.

is a smut fungus that obligately infects and stimulates tissue swelling to form galls. Unlike T-type, MT-type can only proliferate within plant tissues and infect the offspring of their host. Production of telispores, haploid life, and plant cuticle penetration are not essential for it, which may lead to the degeneration in these processes. Transcriptome changes during the mating of T- and MT-type were studied. The functions of several secreted proteins were further confirmed by knock-out mutants. Our results showed that MT-type can receive environmental signals in mating and circumstance sensing as T-type does. However, MT-type takes a longer time for conjunction tube formation and cytoplasmic fusion. A large number of genes encoding secreted proteins are enriched in the purple co-expression module. They are significantly up-regulated in the late stage of mating in T-type , indicating their relationship with infecting. The knock-out of (xylanase) resulted in an attenuated symptom. The knock-out of or (function unidentified) completely blocked the infection at an early stage. This study provides a comprehensive comparison between T- and MT-type during mating and identifies two candidate effectors for further study.