exam 3 (lect 23) Flashcards
later diverging lineages
ascomycota and basidiomycota
sister MONO phyletic groups
coencytic
early diverging fungal lineages do not have consistent partitions between cells
fungal mycelium
madee up of cells containing multiple nuclei and continuous cytoplasmic conncetions
septate
dikaryotic fungi
consistently partitioned by cross walls
ex. neurospora (asco)
ganoderma (basid)
asco septal porosity
Woronin bodies (tethered balls), septal pore proteins plug septal pores, allow high velocity flows
basid septal porosity
dolipore septa with caps (aka parenthesomes)
septal pore swelling)
dolipore (central pore in septum)
non-newtonian septal flow
newtonian - symmetrical flow rates on both sides
NOT true in fungal hyphae
slow down as go through septa
septa functional roles
- protect against terminal leakage
- compartmentalization
- separate mother and daughter cells
- ensure correct nuclei are present following cell division
plasmogamy
cells fuse together but not nuclei
karyogamy
nuclei fuse together
dikarya
decoupled plasmogamy and karyogamy
N+N
two genetically distinct haploid nuclei at same time
dikaryon
dikaryotic hyphae present
in two major fungal lineages (asco, basid)
>95% of species in kingdom
derived state!!
split gill fungus experiment
fungal evolution of dikarya
schizophyllum commune (basid)
test for increased growth speede
monokaryons v dikaryons in growth speede
mono - avg growth is faster
dikary - slower rate but able to increase rate over change and potentially grow faster
evolutionary benefits of dikaryon
if deleterious mutation in one nuclei, other compensates for it
phenotypic plasticity
masking/unmasking allelic/genotypic variation
ascomycota
64000 (1/2 of known fungi)
MONO phyletic
ascomycota: habitat, ecology, growth form, septation
habitat: both teerrestrial and aquatic
ecology: free-living, symbionts
growth form: hyphal and unicellular (some dimorphic)
septation: present!
asco key features
spores in ascus (sac)
diaryotic stage shorter compared to basid
Woronin bodies
crozier cells (isolate nuclei)
asco life cycle
conidiophores and conidia (asexual reproduction)
asocarp is outer wrapping for spore bearing surface
croziers hold N+N nuclei in one cell
2X meiosis 8 N spores
asexual spores not contained in sporangium
famous asco
morchella esculenta (state shroom) penicillum chrysogenum (=notatum) - antibiotic penicillin tuber gibbosum (truffle)
pseudogymnoascus destructans
causes white nose syndrome in bats
why does penicillium have 2 names?
penicillium macrosporum (asexual)
equal to Talaromyces macrosporus (sexual spores)
Named based on teleomorph/sexual stage!
basidiomycota
species richness 32000 species (.5 of asco)
MONOphyletic
basidiomycota: habitat, ecology, growth form, septation
habitat: terrestrial majority
ecology: saprobes (Decomposer), pathogens, symbionts
growth form: hyphal and unicellular
septation: preseent!
basid key features
spores on basidia (club)
clamp connections
dolipore septa (cap, swelling)
longer dikaryotic stage
basid life cycle
dikaryotic throughout vegetative state (unlike asco)
4 spores as result of 2X meiosis
clamp connections
basid
temporarily bridge terminal hypha with cell behind it
allows nuclear migration during mitosis
ensures each cell has a set of differing nuclei
famous basid
mushrooms (agaricomycotina, amanita)
rusts (pucciniomycotina)
smuts (ustilaginomycotina), corn pustules
entorrhizomycota
new phylum in dikaryotic clade
sedge (grass like plant) with fungal galls on roots
hyphal spirals and packets of spores inside gall
entorrhiza fungi morphologiy
septal pore has pore swelling at tip like dolipore (basid)
gall structure
new MONOphyletic group
needs genome for phylum status resolve
organisms in lichen
mycobiont + photobiont
myco - fungi, heterotroph, does not make C
photo - algaee or cyanobacteria
lichen symbiosis
get name from fungal partner (mycobiont)
multiple origins, independently evolved
cyanobacteria photobionts are monophyletic but NOT algal
where do lichens live?
all types of land enviros
dominate more land surface than tropical rain forest
most abundant in extreme enviro (high/low temps, low precip, high light)
ex antarctica: 2 plant speciees, over 350 lichen species that grow inside rocks for protection
lichen morphology
thallus body
parter in photobiont layer
huastorium - plug like structure that takes sugar alcohol produced by photobiont, projection that can penetrate tissue
lichen reproduction
soredia - dusty surface, wrapped up algae and hyphal
linked propagules - fragments, isidia
asexual reproduction –> keeps symbionts together
apothecia - cup-like fungal structure
sexual requires de nono associations, separate symbionts
lichen growth
SLOW
depend on air and rain for all nutrients to diffuse into surface (no roots)
no outer cuticle layer –> sensitive to moisture and enviro changes
poikilohydric, opportunistic growth
lichen photosynthetic ratees
lecanora muralis
early breakfast response
highest water content in early morning, not too much light, highest photosynthesis
how do lichens tolerate extremes
- boundary layer - temp and wind dessication diff, lower to ground
- when thallus drying, sugars pumped into cells to fill space and stabilize cell structures, suspension of cell NOT collapse
- in dessicateed state, not damaged by temp and light extremes (poikilohydric)
- living in symbiosis, partners can prod molecules that reduce enviro stress (ex. high light increase oxygen radicals which is dnagerous to cell)
schwendener 1869
lichen symbiosis described as parasitisim by fungi on photobiont
kanner et al 2005
is lichen symbiosis a mutualism? stress tolerance cladonia vulcani (fruticose reindeer licheen)
O2 radical (ROS) scavenging
formed during desiccating conditions
Fungi
Alga - use GSH, alpha tocopherol, beta-carotene
fungal - use only GSH (glutathione)
cladonia vulcani
fruticose reindeer lichen
mycobiont cladonia vulcani
photobiont trebousxia excentrica (algae)
comparison of ROS scavenging lichen symbiosis
algae better able to deal with desicaction
fungi has better stress tolerance and is more similar to undesiccated with partner
Wila study
bryoria fremontii (edible, brown) bryoria tortuosa (toxic, yellow, vulpinic acid) cannot be distinguised as separate either as mycobiont or photo
metatranscriptomics of mycobiont
look at what is upregulated in both wila species
asco and alga in both
Basidiomycota in yellow wila, tortuosa
cryptic fungus
in rust clade, cyphobasidiales
byoria tortuosa yellow wila
vulpinic acid
unknown if yeast producese acid or somehow stimulates productions by ascomycete mycobiont
where are yeast/basids located in thallus
upper layer of cortex within mycobiont, on top
