1. Dikaryomycota Persistent dikaryon: cells with two haploid nuclei Regularly septate hyphae

2. Dikaryomycota – two haploid nuclei Haploidy  nuclear condition, referring to number of chromosome copies per cell in G1 G1 G2 SM

3. Dikaryomycota – two haploid nuclei Nuclei: Haploid Dikaryotic Diploid plasmogamy karyogamy ?

4. Dikaryons in fungi Only one cell – Zygomycetes Limited dikaryon – Ascomycetes Persistent dikaryon – Basidiomycetes

5. monokaryon dikaryon

6. Maintaining the dikaryon state Conjugate mitosis – coordinated nuclear division Typically at “clamp connections” that have specialized septa

7. Simple septum vs Dolipore septum

8. Dikaryomycete classes based on sexual sporulation Ascomycetes  in sacs Basidiomycetes  on stalks

9. Ascomycete life cycle Asexual cycle: haploid spores (n) +/– mating types septate hyphae (n)

10. Ascomycete life cycle, Raven 15-14 Asexual cycle: haploid spores (n) +/– mating types septate hyphae (n) ascogonium trichogyne antheridium plasmogamy Mating structures: Trichogyne growth Nuclear migration

11. Ascogonia and antheridia An As T

12. Ascus development crozier karyogamy 2n meiosis I meiosis II mitosis (sp dep) germination

13. Ascus formation Crozier = hook penultimate cell  karyogamy Meiosis and mitosis in developing ascus

14. Ascus development meiosis I meiosis IImitosis karyogamy

15. Ascomata: four types Peziza Morchella Neurospora Magnaporthe Emericella Erysiphe Cochliobolus Note ascus shape: elongate vs spherical

16. Elongate asci: 2 types unitunicatebitunicate operculum pore Cleistothecial asci

17. Asci and ascospores Peziza Eurotium Otidea

18. Ascoma development dikaryotic ascogenous hyphae (n+n) Sterile Hyphae (n) croziers Ascogonium

19. apothecium perithecium Ascomycete fruiting bodies: ascomata

20. Mycosphaerella pseudothecia

21. Erysiphe graminis

22. Heterobasidia Holobasidia Synchronous spore formation Asynchronous spore formation septa sterigma basidiospore Nuclei migrate through the sterigma/spore junction

23. Mushroom life cycle 15-19 Basidiomata initiation is triggered by environmental conditions, including moisture Dikaryotic hyphae

24. Mushroom development Hymenium – fertile layer Mushroom hymenium on: _____, _____, _____

25. Lactarius indigo Gilled mushrooms Agaricales

26. Pores are lined with basidia

27. Fomes fomentarius

28. Hydnum repandum Auriscalpium vulgare

29. Deuteromycetes – life without sex

30. Advantages – speed (of reproduction, ~1 day) – flexibility (can maintain a well-adapted genome) – can maintain (lethal?) mutations in haploid nuclei, since hyphae are multinucleate