Mating gene in Fusarium oxysporum (related articles)
Mating type loci in Fusarium:
Structure and function
Waalwijk, C., Keszthelyi, A., Van Der Lee, T., Jeney, A., De Vries, I., Kerenyi, Z., … Hornok, L. (2006). Mating type loci in Fusarium: Structure and function. Mycotoxin Research, 22(1), 54–60. https://doi.org/10.1007/BF02954558
genetic factors effecting sexual reproduction
in toxigenic fusarium species
Hornok, L., Waalwijk, C., & Leslie, J. F. (2007). Genetic factors affecting sexual reproduction in toxigenic Fusarium species. International Journal of Food Microbiology, 119(1–2), 54–58. https://doi.org/10.1016/j.ijfoodmicro.2007.07.026
Molecular background of sexual
reproduction
deletion of MAT genes modified
transcript profile of mutants
conclusion of review paper
introduction
An Overview of the Function and Maintenance of Sexual Reproduction in Dikaryotic Fungi
Wallen, R. M., & Perlin, M. H. (2018, March 21). An overview of the function and maintenance of sexual reproduction in dikaryotic fungi. Frontiers in Microbiology. Frontiers Media S.A. https://doi.org/10.3389/fmicb.2018.00503
major source of variation, meiotic recombiantion
asexual fungi, high mycotoxin production
mycotoxin is secondary metabolite,
same mycotoxin profile
but differ in quantitative production.
homothallic: complete sexual
cycle by mating themselves (MAT1 &MAT2)
heterothallic: need partner to complete sex cycle either
MAT1/MAT2
MAT loci being transcribed asexual F. oxysporum
MAT 1: MAT1-1-1, MAT1-1-2,MAT1-1-3
MAT2: MAT1-2-1
MAT1-1-1 and MAT1-2-1 is major regulators in sexual
communication as they carry α-box domain and HMG-box
MAT1-2-1 mutant: down regulated genes are the genes
that have role in matiing
suggest that MAT gene products have multiple
regulatory roles
can study the genes regulation
female sterility-reduced female
fertility
deletion in
homothallic: cause female sterility
hetero: cause both female and male sterility
cause of female sterilty
host preferences
block by FpmtrI- amino acid transporter
gene.express
might function as
sensor /receptor protein
Fphch gene (conserved in
G.fujikuroi)
inactivation reduces sexual fertility
MAT genes in asexual fungi
regulated other portions of life cycle
in MAT1-2-1 deletion
numerous up and down regulated gene
involve
loss of female sterility might cause
the shift toward asexual cycle
introduction
advantage of sexual &
asexual
asexual: suit that already
adapted to particular env.
sexual: can lead to change of
gene pool and increase infection
and spread in host
synteny of mating type locus btween
Fusarium spp.
Gene expressing profiling
Function of mating genes
in Fusarium spp.
sexual struct similar to
sexual relatives: F. verticillioides and F. proliferatum
MAT1-2 mostly used,
HMG-box highly conserved
across fungal kingdom
control pheromone genes and
genes encode pheromone receptors
asexual of individual fungi might due to
other gene tht required for mating
give mating identity
Deletion of MAT1-2 in
F.verticilloides
60 clones of known
protein upregulated and 57
dwnregulated
nitrilase: biosynthesis
signalling molecules
opsin like protein: light response
protein involve in stress response
introduction
Fusarium oxysporum
sexual repro: to improve
strains (plant pathogen, industrial)
meiosis serve as DNA
damage repair
contain novel type of peptide
precursor.
pheromone precursor : sensing/ sending signals
to potential host plant
in plant patho interaction
they can sense the host and
grow in that direction
fungal hyphae moved based on peroxidase
release by plants.
pheromones results in chemotrophic
response
signals received by the pheromone receptor can change the growth of the fungal hyphae in the direction of a potential host
The roles of sexual and asexual reproduction in the origin and dissemination of strains causing fungal infectious disease outbreaks
Ashu, E. E., & Xu, J. (2015). PT. MEEGID. https://doi.org/10.1016/j.meegid.2015.09.019
introduction
Emerging modes of fungal infectious disease outbreaks
The role of sexual and asexual reproduction in the introduction of novel strains
The role of sexual and asexual reproduction in outbreak expansion
pathogenic fungi they are able to:
-adhere to host surfaces
-penetrate host external surfaces &migrate
-circumvent host defense & multiply
genes involve in pathogenic
get through gene duplication,
mutation & selection
external factors known to influence
asexual and sexual reproduction
infectious disease outbreak
introduction of novel strains
significant changes to
host population
changes to the envi from
which host pathogen interact
exotic introduction of existing or novel fungal strains from one location to another new geographic environments
basexual repro & mutation
generation of novel strains
by sex repro, including HGT
asex: can initiate disease outbreaks
by complex duplication& deletion
events
asexual fungi: have large no of
mutation that lead to fixation
of a better mutants
generate novel strain from sex dev
once pathogen adapt toward host envi
relative amount of sexual&
asexual occurring reproduction
can estimated based on female
fertile strains.
evolution of asexual repro
can induce rapid and permanent loss
of sexuality
sex and asexual work synergistically
in outbreak expand
fungal outbreaks expanded
asexually
outbreak started with sex recombination.
-due to adaptation, asexual repro
takes place
RESEARCH PAPER (LATEST)
Structure-activity relationship of α mating pheromone from the fungal pathogen Fusarium oxysporum
Vitale, S., Partida-hanon, A., Serrano, S., & Martínez-del-pozo, Á. (2017). Structure-activity relationship of α mating pheromone from the fungal pathogen Fusarium oxysporum. https://doi.org/10.1074/jbc.M116.766311
INTRODUCTION
to understand how
α-pheromone interact, activate cognate GPCR Ste2, which play role in chemotrophic grow toward host
3D structure of α-pheromone reveals
the presence of central β-turn essential for chemoattractant activity
The
structural characteristic
of α-pheromone in
F. oxysporum
In S. cerevisiae, mating gene secretes
phermones peptide (a&alpha)
function: sexual chemoattractant.
move toward opposite mating type
alpha factor plays role in
receptor activation, signaling pathways
BUT
In ascomyctes, alpha pheromone
share low no seq similarity in yeast
F. oxysporum, α-pheromone
have chemoattractant activity
shorter peptide, and gave 2 cystein,
(disulphide bond)
presence of 2 cysteines in F. oxysporum but the regulation still unknown
both have β-turn, a charged residue (Arg in F. oxysporum and Lys in S. cerevisiae)
act as molecular
antenna , role in intermolecular
interactions
3D struc resembles in
S. cerevisiae
conclusion
α-pheromone elicits a robust chemotropic response in germ tubes of F. oxysporum, which is dependent on the cognate GPCR Ste2
- both contain central
β-turn with AA
chenoattarction require
G6 & Q7, not W1 &C2
G6 & Q7 maintain the 3D structure
suggest tht, activation
Ste2 mediated chemotropic
growth depend on secondary β-turn structure of α-pheromone
α-pheromone have defined
structure
α-pheromone involve in
diff biological process
-polarity orientation
-cell cycle control
MOLECULAR IDENTIFICATION OF MATING TYPE GENES IN ASEXUALLY REPRODUCING FUSARIUM OXYSPORUM AND F. CULMORUM
Sex-specific gene expression during asexual development of Neurospora crassa
Presence and Functionality of Mating Type Genes in the Supposedly Asexual Filamentous Fungus Aspergillus oryzae
female fertile are favoured in sexual
reproduction
CONTINUE..
Autocrine pheromone signalling regulates community behaviour in the fungal pathogen Fusarium oxysporum
Functional analyses of individual mating-type transcripts at MAT loci in Fusarium graminearum and Fusarium asiaticum
introduction
F.graminearum is homothallic pathogenic fungi
causal agent of Fusarium head blight
carry another MAT gene that was MAT1-2-1 but no effect on sexual reproduction
from study, MAT1-1-1 and MAT1-2-1 are essential for mating and mating type specificity
conclusion
in MAT1-1-1 mutant, they produced smaller and thicker perithecium walls, indicate importance in perithecia formation
the MAT1-1-1 mutant are reduced in virulence in corn stalk assays conducted
in out crosses, mat1-1-1 mutant displayed male-specific defect, although normal in female fertility
in post perithecial induction, MAT1-1-1 and MAT1-1-2, the expression peaked at 1 dpi
MAT1-1-1 may have enhanced sensitivity in overcoming other plant defensive response (phytoalexins)
approach used in identification of mating genes
molecular identification
PCR reaction
targetting alpha box & HMG box domain
to conclude that, F.oxysporum and F.culmorum have a potentially heterothallic origin
no sexual structure observed must be caused due to something other than MAT
asexual F.oxysporum and F.culmorum have been detect MAT genes
study the expression level for both mating types throughout vegetative dev
characterized for
mating types genes
pheromone precursor and receptor
genes related to conidiation
light responsive genes
level of conservation within eukaryotes
regulation of expression of pheromone precursor and receptors from mating type genes
the receptor expression pre-1 in mat A show same pattern peak at 60h
in this study, no evidence of sexual reproduction being observed
the expression of ccg-4 and mfa-1 xsolely depend on mat gene
pre-pheromone encode by ccg-4 and mfa-1 being translated into mature pheromone
cryptic sex in fungi
overview of the articles
sex preserves beneficial and removes deleterious mutations
MAT is used to differentiate their sexually compatible
asexual spores producers: deuteromyctes/fungi imperfecti
sex will combine a good traits from 2 parents provide offspring that can survive in changing env
in some asexual fungi, their sexuality can be induced (Candida albicans
now: mitosporic/anamorphic fungi
in Aspergillus fumigatus, their MAT1, pheromone receptor and other sex genes is being expressed.
sex was induced MAT1-MAT2 for 6 month,
its considerd that sex cycles knowledge will greatly facilitate future sexual crossing approach
demonstrated that, cryptic sexual cycle will be importance to understand how diverse fungi evolved,
fundamentals for potential applications
orchestration of sexual reproduction and virulence by the fungal mating type locus
overview of the articles
sex and virulence
Malassesia globosa
structure and evolution of MAT locus (ustilago hordei)
molecular struc of MAT 1st characterized in S.cerevisiae
in basidiomyctes, a loci: encode pheromone funct as cell signalling during mating
b loci: transcribes 2 homodomain protein to express gene involve in completing the cycle
diff in size
reside on human and animal skin
share the same homology with U.hordei
the sequence a and b lack of repititive sequence
in rust fungi,cells unable to mate are avirulent;cant produce filementous struct to grow
sex serves as defending mechanism for virus infection
mating is rare, low chance of mating.distribution of a and b loci
ssexual cycle vital in generate spores, cause infection
fungal sex receptors recalibrated to detect host plants
pathogenicity of the F.oxysporum start with choosing the right host to infect
fungi survivality based on suitable host plant and ability to overcome host defense
plant will produce chemical by which to attract beneficial relay with m/o
exp: produce hormones, strigolactones that attarct mychorrhizal fungi.
to combat pathogenic fungi, the root produce various antimicrobials
F.oxysporum hijack this E. activity by migrate toward tomato roots, and colonized.
Mitogen activated protein kinase signalling cascades involve
mutant lack MAPK cascades lost ability in sensing peroxidase
pathogens track the host tru peroxidase serve as reporter of wounded sites
but how F.oxysporum manage to overcome antimicrobial peroxidase
mat gene were increasingly expressed over asexual course
Fungal mating pheromones: Choreographing the dating game
Sex and Virulence of Human Pathogenic Fungi
Orchestration of sexual reproduction and virulence by the fungal mating-type locus
Mating in mushrooms: increasing the chances but prolonging the affair
Transduction of pheromone signal
recognize by G-protein coupled receptors
best studied GPCR in S. cerevisiae
GPCR recently, involved in mating
The MAP Kinase signalling cascade
pheromone activation of GPCR initiate sgnal transduction cascades-MAPK pathways
activation of ste12, the T.factor req for mating
Mating MAPK signalling cascade 
output from pheromone signalling
Ste12 mediated T.of genes involve in mating
formation of polarized mating projections-promote growth 2ward mating partner
G1 cell cyle arrest-allow fusion of unreplicated nuclei during karyogamy
post cell fusion roles for mating pheromones
pheromones essential for events lead to cellular fusion
use spheroplast to induced fusion efficiently
budding yeast of mating system
pheromones secreted as chemoattractant-cell fusion
the pheromones and receptors
2 type of pheromones
2 types of receptor, Ste3p and Ste2p
mating happen in mushroom, carry A and B gene
Ustilago maydis, carry same set
Prf1 -pheromone respone factor in U.maydis
clp1 and pcc1 -regulating clamp-cell development
however, no role of cAMP pathway in mating in mushroom still unknown
sex related not only fitness but also virulence
dandruff fungus-Malassesia globosa,mating occur in host skin
ustilago maydis
sex and virulence
some pathogenic fungi only will produced infectious struc after mating
cell cant mate, fail to cause pathogen
mating need cues from host to complete sexual cycle
in ascomycetes, spores vital to cause infection
sex reproduction-mantain virulence traits
potential to retain in population
human pathogenic fungi
most common, Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus
ability in cause disease, relate to sexual reproduction
MATING TYPE LOCI-sex determining
in ascomyctes, bipolar mating syst
pheromone important in formation of heterodimer and mate
fungi have either bipolar or tetrapolar mating syst
mating type locus in A. fumigatus
genes for pheromones, receptor and components for pheromone signalling pathway identifies
mat is express3ed and suggest it may competent for mate
role of sex in pathogenesis
spore is the main pathogenic in the fungi
sex reproduction not observed in cryptococcus
alpha mating type is more virulent compare to a strain
but they r infectious
structure and function of mating type genes in Cochliobolus spp. and asexual fungi
mating type genes in ascomycetes
ascomycetes have bipolar mating syst
mating specific homologs are functionally interchangeble among species
cochliobolus heterostrophus MAT deletion strains
constructed gene using gene replacement method
all deletions cause complete sterility
mating identity can be switched, by replacing with others
heterologous expression
when mat gene from related species transformed into C.heterostrophus, they become homothallic
indicate MAT gene is well conserved
ascospores production involve MAT transgenes
Management of fusarium wilt of banana: special reference to Tropical race 4
banana host
most valuable agricultural commodities
staple food in africa, asia, tropical america
most significant group, Cavendish type
most important export
Fusarium wilt
wide range of host disease
most destructive in all plant disease
TR4 was competent in good soils
they infect roots of susceptibles cultivars
over 20 VCG are recognized in the pathogen
race 4 affect race 1&2 susceptible cultivars
epidimiology
foc survived decade in soils and banana free rotation ineffectives
chlamydospores (stay dormant)
insects might be a vector disease
management
quarantine and exclusion
cultural measures
chemical measures, fungicides
physical measures
Biocontrol
Sex-specific gene expression during asexual development of Neurospora crassa
N. crassa, heterothallic model fungi-bipolar mating sytem
regulatory interactions with mating type complicate conidial gene expression
mating type genes showed no mating type specific regulation on expression of pheromone
mat a-1=encode HMG box
mat A= carry 3 genes, alpha box
pheromones being maintaines in asexual life cycle
mating specific expression in P. anserina, S. macrospora: metabolism, information pathway, transport and developmental pathways
ccg gene (conidial gene)
ccg being expressed similar in both loci
con 8 is expressed in older cultures at a high level
expression of ccg4 and mfa-1 being observed
mutant of ccg and mfa1 is totally lost fertility
mutant showed no chemoattarctant activityand exhibit normal protoperithecial dev
pre-pheromoned encode by ccg4 and mfa1, transcribed and translated
dev of protoperithecia require growth conditions