Tag Archives: fungal

Postdoc positions at Duke University & MMTP

Postdoc positions in the Heitman lab and through the Molecular Mycology Training Program at Duke University, NC State, and University of North Carolina are available as of December 1, 2014.

HeitmanImageThe Heitman lab at Duke University is seeking Postdoctoral Fellow applicants. The lab focuses on molecular determinants of development and virulence in the pathogenic basidiomycetes Cryptococcus neoformans and Cryptococcus gattii with complementary studies in both model and pathogenic fungi including Cryptococcus amylolentus, Filobasidiella depauperata, Cryptococcus heveanensis and other related basidiomycetes including Kwoniella and Malassezia species, species from the Candida pathogenic complex (C. albicans, C. lusitaniae), and the zygomycete Mucor circinelloides.

Areas of research interest include:

  • modes and impact of unisexual and sexual reproduction
  • structure, function, and evolution of the mating type locus
  • calcineurin in fungal virulence and as a novel antifungal drug target
  • comparative fungal genomics of a species cluster of human fungal pathogens
  • molecular networks that orchestrate infection of the host and development
  • RNAi based pathways operating during mitotic and sexual development and epimutational gene silencing
  • mechanisms of action of natural products and antifungal drugs

Applications should send pdfs of curriculum vitae, reprints/preprints, a statement of research accomplishments and interests, and letters of recommendation to Joseph Heitman at heitm001@duke.edu.

Attend Fungal Genetics 2009!

If you are interested in fungal genetics and genomics, comparative biology, and of course dancing with fungal geneticists, plan to attend the 25th Fungal Genetics Meeting held at the beautiful Asilomar Conference Grounds in Pacific Grove, California. Below is info sent out from the Policy Committee and registration opens in a little over a month.  Budding (and conidiating) artists can also submit a Logo design so we have cool T-shirts to wear.

25th Fungal Genetics Conference Registration and Program

The Fungal Genetics Policy Committee invites you to attend the 25th Fungal Genetics Conference, sponsored by the Genetics Society of America.   The meeting will be held March  17-22, 2009 at the Asilomar Conference Center, Pacific Grove, California (near Monterey, California).

The FGSC is pleased to announce that the scientific program and registration information are available online at the FGSC website

Registration for the meeting will take place online at the FGSC and GSA websites from October 27th-December 12th.

Financial aid applications are due November 14th.

Abstract submission deadlines are the same as the registration deadlines, from October 27th to December 12.

LOGOS – Please Submit your artwork

We are also pleased to invite the submission of logos for the meeting. Past logos are available for review

The winner will receive a complimentary t-shirt.

Please send logos to the FGSC by October 17, 2008.

Bats beware of white nose

An outbreak of a fungal infection called “white-nose syndrome” is killing bats in the Northeastern US.  This New Scientist article mentions the outbreak briefly and an NPR story and recent Boston Globe story also gives it some coverage.  Sounds like we still don’t know much about the causal agent or how it is killing the bats at this time, but some researchers, including Elizabeth Buckles at Cornell University, Vishnu Chaturvedi at NY State Dept of Health, and Jon Reichard at Boston University are working on it.

This is of course old news if you read what Hyphoid Logic has been saying.

That there is a previously undescribed cold loving fungus sounds very interesting, there have been some recent discoveries of psychrophilic fungi like Cryptococcus laurentii and Rhodotorula himalayensis so it would be interesting to learn more when the researchers publish some of these results.

Some more links

Thanks Kathyrn B for reminder about this story.

Dermatophyte genome sequences

The first of several dermatophyte fungal genomes, Microsporum gypseum, has been released at the Broad’s Dermatophyte site.  Two Tricophyton species and another Microsporum genome should follow soon. These dermatophyte fungi are Onygenales (Ascomycota) fungi (like Coccidioides and Histoplasma), although their placement in the phylogenies shown in the whitepaper and related review paper is a bit ambiguous. I’m sure that can be improved with a few more gene sequences gleaned from the genomes.

The 23 Mb M. gypseum genome is a bit smaller than the sizes of C. immitis (28 Mb), H. capsulatum (32 Mb), or Paracoccidioides brasiliensis (29 Mb).  While no annotation is currently available for the M. gypseum genome, this genome will help in establishing what genes were ancestral in the Onygenales and comparing patterns of gene family gains and losses in fungi that specialize on animal hosts.

Some more comparison across different kinds of dermatophyte fungi that are very distantly related like dandruff causing fungus Malasezzia globosa (Basidiomycota) will be really interesting as well.

Thanks Joe H and FGI folks for passing along announcement and to the Broad/FGI folks for the work to make this sequence available.

A word about databases

Logo for fungal GenomesReport concludes that a fungal genome database is of “the highest priority”.

This is the title as listed in PubMed for this article from Future Medicine about the AAM report on charting future needs and avenues of research on the fungal kingdom.

The need for a comprehensive database for information about fungi, starting at least with systematic collections of genomic and transcript data, is highlighted as a major need.  Really and sort of new database effort should strive to be more comprehensive and include genetic and population data (alleles, strains) and information like protein-protein, protein-nucleic acid interactions (as Pedro mentioned). But on top of that it, it needs to be comparative so that information from systems that serve as great models can be transferred to other fungal systems that are being studied for their role as pathogens or interacting in the environmental.

Affordable next-gen sequencing will allow us to obtain genome and transcript sequence for basically all species or strains of interest.  Researchers with no bioinformatics support in their lab will likely be able to outsource this to a company or campus core facility.  But how can they easily map in the collective information about genes, proteins, and pathways onto this new data?  And have it be a dynamic system that can update as new information is published and curated in other systems.

I think this has to be the future beyond setting up a SGD, CGD, etc for every system.  The individual databases are useful for a large enough community where there are curators (and funding), but we will have to move to a more modular system in the future (aspects of which are in GMOD) that can have both an individual focus on a specific species/clade and a more comprehensive view of the that is comparable across the kingdom.  There are 100+ fungal genomes, but the community size for some of them are in the dozens of labs or less. How can they take advantage of the new resources without an existing infrastructure of curators?  Their systems serve an important need in a research aim, but how can discoveries there make its way back into the datastream of othe systems?

I see it as there are several ways one would interact with a system that provided single-genome tools as well as a framework for comparative information.  At a gene level, one might be looking for all information about a specific gene, based on sequence similarity searches, or starting with a cloned gene in one species. Something akin to Phylofacts or precomputed Orthogroups for defining a Gene but with more linking information about function by linking in information from all sources.  So a comparative resource, but also tapping into curated andliterature mined data.

At a genome level, one might want to do whole genome comparisons of gene content from evolutionarily defined families genes (gene family size change) or at a functional level.  To start out with, each gene/protein would already need a systematic functional mapping.  This could be as simple as running InterProScan on every protein, expanded to find Orthogroups (or OrthoMCL orthologs) and transfer function from model systems, and finally even more advanced, do further classified better with tools like SIFTER.

Interlinked with these orthologous and paralogous gene sets would be anchors for analyses of chromosomal synteny and even comparative assembly including tools like Mercator.  Certainly things like all of this exist but making it more pluggable for different sets of species would be an important additional component.

At a utility level, the gene annotation and functional mapping of all this information should be possible. I would imagine a researcher could upload the sequence assembly they received from the core facility and the system can generate multiple gene predictions, annotate the genes, and link these genes within the known orthogroups of the system (preserving their privacy for these genes if desired).  Presumably this sort of thing would be easier as a standalone in-house for the researcher, but web services could also be the place for this.

For fungal-sized genomes this amount of data is not too extereme.  Things like Genome Browser, BLAST, etc should all be rolled out of the box based on the basic builds.

On the DIY and community annotation front, there would also need to be a layer of community derived annotation that could be layered on all these systems.  I would imagine this both to be for gene structure annotation (genome annotation) and functional annotation (protein X does Y based on experiment Z, here is the journal reference).  I think aspects of this would be visible, auditable (tracked), but maybe not blessed as official until a curator could oversee these inputs. In my mind, whether or not this is in a Wiki per se or just new system that allows community input is less important to me than having it be a) structured (not a bunch of free text) b) tracked and versionable c) easy for researchers to input so that the knowledge is captured, even if it has to be reorganized later on.

Seems like a lot of work to be done, but really many of these things already exist through what  the GMOD project has built.  Many loose ends and software that doesn’t fully meet up to these needs, but I think the important concept is these are all general solutions that will be of benefit to most communities, not just the fungal ones.  One lingering question I always have when approaching genomic datas

that will be dynamic, what if any of this makes its way into GenBank?  How is this sort of thing banked so that it can be captured, and does the improved functional or gene structure annotation ever make its way into the repository databases to correct and improve what has already been submitted there?

AAM Releases “The Fungal Kingdom” Report

AAM The Fungal Kindgom Report CoverThe American Academy of Microbiology has released a report (PDF and archived on fungalgenomes.org) on the Fungal Kingdom outlining importance of research in the kingdom and recommending several areas of priority for future areas of research.

One recommendation that makes the top of the list is an integrated database for fungal genomes, something we’re keenly interested in seeing happen.  This sort of centralized repository of functional annotation, literature links, and genome sequences and annotation is critical given the 150+ genomes that are available or on their way.  Systematic re-annotation with consistent tools, comparative analyses and gene predictions, and linking gene sequences by homology and ortholog predictions are a critical component to fully utilizing the genomic data that has been produced for the fungi and other organisms.

Amphibian skin bacteria shown to fight off Batrachochytrium dendrobatidis.

A year ago researchers at James Madison University discovered that, Pedobacter cryoconitis, a bacteria first found on the skin of red backed salamanders, was found to prevent the growth of the chytrid B. dendrobatidis, which is currently decimating frog populations.

(Mountain Yellow-Legged Frog from wikipedia)

The newest research on the subject is being presented this year at ASM by Brianna Lam who worked with other biologists from both San Francisco State University and JMU.

Lam’s research indicates that adding pedobacter to the skin of mountain yellow-legged frogs would lessen the effects of Batrachochytrium dendrobatidis (Bd), a lethal skin pathogen that is threatening remaining populations of the frogs in their native Sierra Nevada habitats.

Lam first conducted petri dish experiments that clearly showed the skin bacteria repelling the deadly fungus. She then tested pedobacter on live infected frogs, bathing some of them in a pedobacter solution. The frogs bathed in pedobacter solution lost less weight than those in a control group of infected frogs that were not inoculated.

In addition to the lab experiments, the JMU and SFSU researchers have studied the yellow-legged frogs in their natural habitats and discovered that some populations with the lethal skin disease survive while others go extinct. The populations that survived had significantly higher proportions of individuals with anti-Bd bacteria. The results strongly suggest that a threshold frequency of individuals need to have anti-Bd bacteria to allow a population to persist with Bd. (from Eureka alert)

The research above is really interesting and I am curious as to how the bacteria is actually killing the chytrid. The only other research I can think of where chytrids were being killed was a BBC news article that wrote about scientists bathing frogs in chloramphenicol.

Deconstructing aflatoxin biosynthesis

A paper in Science from Jason Crawford and colleagues explores the function of polyketide synthetases (PKS) in the synthesis of the secondary metabolite and carcinogen aflatoxin. Previous work (nicely reviewed in the fungi by Nancy Keller and colleagues) has shown the the PKS genes have several domains. These domains include acyl carrier protein (ACP), transacylase (SAT), ketosynthase (KS), malonyl-CoA:ACP transacylase (MAT), “product template” PT, Aand thioesterase/Claisen cyclase (TE/CLC).  These domains make up PksA, but the specific role of each domain’s in synthesis steps has not been fully worked out. Understanding this process and the specificity of the chemical structures that are created can help in redesign of these enzymes for synthesis of new molecules and drugs.

Then authors cloning and combining the domains from a cDNA template of pksA [accession AY371490]  (from Aspergillus parasiticus) into various combinations and then evaluated the synthesized products via HPLC.  This deconstruction of a complicated protein and its domains is a great example of functionally mapping the role of each part of the enzyme and integrating with the biochemistry of the synthesized products.  The findings of this research also mapped a role for the PT product template domain which could suggest where modifications could be made to tweak the synthesized products by these enzymes.

Crawford, J.M., Thomas, P.M., Scheerer, J.R., Vagstad, A.L., Kelleher, N.L., Townsend, C.A. (2008). Deconstruction of Iterative Multidomain Polyketide Synthase Function. Science, 320(5873), 243-246. DOI: 10.1126/science.1154711

Summer 2008, Mycological Meetings

A few of the summer meetings that relate to fungal biology and evolution. 

Hope to see you at some of these.

More RIP without sex?

In followup to the Aspergillus RIP paper discussion, Jo Anne posted in the comments that her paper published in FGB about RIP in another asexual species of fungi also found that evidence for the meiosis-specific process of Repeat Induced Point-mutations (RIP).

Continue reading More RIP without sex?