A termite symbiotic mushroom maximizing sexual activity at growing tips of vegetative hyphae

Huei Mei Hsieh, Mei Chu Chung, Pao Yang Chen, Fei Man Hsu, Wen Wei Liao, Ai Ning Sung, Chun Ru Lin, Chung Ju Rachel Wang, Yu Hsin Kao, Mei Jane Fang, Chi Yung Lai, Chieh Chen Huang, Jyh Ching Chou, Wen Neng Chou, Bill Chia Han Chang, Yu Ming Ju

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Background: Termitomyces mushrooms are mutualistically associated with fungus-growing termites, which are widely considered to cultivate a monogenotypic Termitomyces symbiont within a colony. Termitomyces cultures isolated directly from termite colonies are heterokaryotic, likely through mating between compatible homokaryons. Results: After pairing homokaryons carrying different haplotypes at marker gene loci MIP and RCB from a Termitomyces fruiting body associated with Odontotermes formosanus, we observed nuclear fusion and division, which greatly resembled meiosis, during each hyphal cell division and conidial formation in the resulting heterokaryons. Surprisingly, nuclei in homokaryons also behaved similarly. To confirm if meiotic-like recombination occurred within mycelia, we constructed whole-genome sequencing libraries from mycelia of two homokaryons and a heterokaryon resulting from mating of the two homokaryons. Obtained reads were aligned to the reference genome of Termitomyces sp. J132 for haplotype reconstruction. After removal of the recombinant haplotypes shared between the heterokaryon and either homokaryons, we inferred that 5.04% of the haplotypes from the heterokaryon were the recombinants resulting from homologous recombination distributed genome-wide. With RNA transcripts of four meiosis-specific genes, including SPO11, DMC1, MSH4, and MLH1, detected from a mycelial sample by real-time quantitative PCR, the nuclear behavior in mycelia was reconfirmed meiotic-like. Conclusion: Unlike other basidiomycetes where sex is largely restricted to basidia, Termitomyces maximizes sexuality at somatic stage, resulting in an ever-changing genotype composed of a myriad of coexisting heterogeneous nuclei in a heterokaryon. Somatic meiotic-like recombination may endow Termitomyces with agility to cope with termite consumption by maximized genetic variability.

Original languageEnglish
Article number39
JournalBotanical Studies
Volume58
Issue number1
DOIs
Publication statusPublished - 2017 Dec 1

All Science Journal Classification (ASJC) codes

  • Plant Science

Fingerprint Dive into the research topics of 'A termite symbiotic mushroom maximizing sexual activity at growing tips of vegetative hyphae'. Together they form a unique fingerprint.

  • Cite this

    Hsieh, H. M., Chung, M. C., Chen, P. Y., Hsu, F. M., Liao, W. W., Sung, A. N., Lin, C. R., Wang, C. J. R., Kao, Y. H., Fang, M. J., Lai, C. Y., Huang, C. C., Chou, J. C., Chou, W. N., Chang, B. C. H., & Ju, Y. M. (2017). A termite symbiotic mushroom maximizing sexual activity at growing tips of vegetative hyphae. Botanical Studies, 58(1), [39]. https://doi.org/10.1186/s40529-017-0191-9