Tag Archives: genomes

Genome survey sequencing of Witches’ Broom

Genome survey sequencing (1.9X coverage) was generated for Moniliophthora perniciosa, the cause of witches’ broom disease on cacao plants. The sequence for this basidiomycete plant pathogen was published in BMC Genomics this week. The authors report a higher number of ROS metabolism and P450 genes. Evaluating whether these copy number differences are significantly different from other basidiomycete fungi and are lineage specific expansions will help determine if these families played a role in the adaptation of this plant pathogen.

This work provides an important stepping stone in understanding and eventually controlling this pathogen which is devastating cacao plantations. An associated review describes what we have and can learn about Witches’ broom disease.

See related:

Jorge MC Mondego, Marcelo F Carazzolle, Gustavo GL Costa, Eduardo F Formighieri, Lucas P Parizzi, Johana Rincones, Carolina Cotomacci, Dirce M Carraro, Anderson F Cunha, Helaine Carrer, Ramon O Vidal, Raissa C Estrela, Odalys Garcia, Daniela PT Thomazella, Bruno V de Oliveira, Acassia BL Pires, Maria Carolina S Rio, Marcos Renato R Araujo, Marcos H de Moraes, Luis AB Castro, Karina P Gramacho, Marilda S Goncalves, Jose P Moura Neto, Aristoteles Goes Neto, Luciana V Barbosa, Mark J Guiltinan, Bryan A Bailey, Lyndel W Meinhardt, Julio CM Cascardo, Goncalo AG Pereira (2008). A genome survey of Moniliophthora perniciosa gives new insights into Witches’ Broom Disease of cacao BMC Genomics, 9 (1) DOI: 10.1186/1471-2164-9-548

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.

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?

Cochliobolus genome released

Just noticed that the JGI has released the Cochliobolus heterostrophus genome sequence at their site predicting 9,633 protein-coding genes.  Torrey Mesa Research Institute had access to a sequence many years ago, but it isn’t until now that public version of this genome is available.  Cochliobolus is has been a model plant pathogen system and its production of T-Toxin by a PKS gene (Yang et al).

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.

Will you always be able to satisfy that chocolate craving?

Crinipellis_perniciosa_mushroomNPR had a story this weekend on Cocoa plantation collapse and the ecological aftermath of the changes the witches’ broom fungus Moniliophthora perniciosa has wreaked. The genome sequence project for this Homobasidiomycete fungus (also known as Crinipellis perniciosa, phylogenetic relationships discussed by Aime and Philips-Mora 2005) is underway at the Laboratory Genomica e Expressao at UNICAMP, Brazil.  The witches’s broom (not this witches’ broom) is named because of the bristly form it induces in the cacao plants.

The genome project will hopefully improve the diagnosis and treatment work that is needed.  Beyond the insatiable need for chocolate, the NPR story does talk about the impact on farmers, the economy, and the environment with the loss of these cacao plantations.

Some links:

I was also browsing some articles on other fungi that inhabit cacao plants and saw a recent survey that includes fungi that produce mycotoxins.

Basidiomycete genomes galore

Just finished attending Genetics and Cell Biology of Basidiomycetes in Cape Girardeau, MO which was an intimate gathering of basidiomycetaphiles.  I learned about systems that are used for studying fruiting body development, genetic mapping, pheromone and mating genes, kinesin dynamics, meoitic gene regulation, and a host of topics.  I’m happy I got a chance to meet more folks in the community and learned about where informatics and computational approaches are really needed to push along some of the interpretation of the more than a dozen basidiomycete genomes.  In particular it sounds like the PleurotusSchizophyllum, Agaricus bisporus, and Serpula genomes are all marching along to completion with some already in 4X assembly or further.  

GCBBVI Group Picture

So we’ll further have more samples from of key model and some less-model species to assist researchers working on many different mushroom-forming fungi that range from brown and white-rotting saprophyte fungi to mycorrhizal fungi that associate with plants.    I’m excited about the work to make transformation and knockouts more readily in these systems too to push the genetics and cellular biology of these systems even further.  The genome sequences will be another tool in these endeavors.

The last day ended with a discussion about genome annotation and future support for curating gene models.  Basically everyone is unhappy with computational predictions and want to be able to go in and fix things. (I think people remember the ones that are gotten wrong more readily than the ones that were right, but computational prediction definitely performs poorly in some situations).   In this Web 2.0-land we live in, this is still not something easily done with any of the freely available genome browsing tools. The JGI’s browser was lauded for its ability to handle these kinds of requests, but how do we proceed when genomes are not sequenced by that center or when (not too distant future) communities are able to sequence a genome themselves using 454/Illumina-Solexa/Helicos/Pacific Biosystems approaches in their own lab?  There is still a huge lag in what kinds of tools researchers can use to annotate genomes to fix gene models and add functions.  Hopefully projects like GMOD will continue to develop useful tools for solving these needs, but there is certainly a need for better support of distributed community annotation of genomes where this little direct money for supporting curators from a single place.

Chlamy genome investigations

Chlamy coverThis month’s Genetics has a series of articles exploring the genome (published last year & freely available at Science) of the green algae Chlamydomonas reinhardtii. These manuscripts are primarily genome analyses making for a very bioinformatics focused issue of Genetics. Some of the highlights include:

Trichoderma reesei genome paper published

TrichodermaThe Trichoderma reesei genome paper was recently published in Nature Biotechnology from Diego Martinez at LANL with collaborators at JGI, LBNL, and others. This fungus was chosen for sequencing because it was found on canvas tents eating the cotton material suggesting it may be a good candidate for degrading cellulose plant material as part of cellulosic ethanol or other biofuels production.  The fungus also has starring roles in industrial processes like making stonewashed jeans due to its prodigious cellulase production.

The most surprising findings from the paper include the fact that there are so few members of some of the enzyme families even though this fungus is able to generate enzymes with so much cellulase activity. The authors found that there is not a significantly larger number of glucoside hydrolases which is a collection of carbohydrate degrading enzymes great for making simple sugars out of complex ones. In fact, several plant pathogens compared (Fusarium graminearum and Magnaporthe grisea) and the sake fermenting Aspergillus oryzae all have more members of this family than does.  T. reesei has almost the least (36) copies of a cellulose binding domain (CBM) of any of the filamentous ascomycete fungi.  They used the CAZyme database (carbohydrate active enzymes) database which has done a fantastic job building up profiles of different enzymes involved in carhohydrate degradation binding, and modifications.

Whether T. reesei is really the best cellulose degrading fungus is definitely an open question.  That it works well in the industrial culture that it has been utilized in is important, but there may be other species of fungi with improved cellulase activity and who may in fact have many more copies of cellulases.  So it will be good to add other fungi to the mix with quantitative information about degradation to try and glean what are the most important combination of enzymes and activities.

One technical note.  The comparison of copy number differences employed in the paper is a simple enough Chi-Squared, work that I’ve done with Matt Hahn and others include a gene family size comparison approach that also taked into account phylogenetic distances and assumes a birth-death process of gene family size change.  It would be great to apply the copy number differences through this or other approaches that just evaluate gene trees for these domains to see where the differences are significant and if they can be polarized to a particular branch of the tree.

So will this genome sequence lead to cheaper, better biofuel production? Certainly it provides an important toolkit to start systematically testing individual cellulase enzymes. It’s hard to say how fast this will make an impact, but the work of JBEI and a host of other research groups and biotech companies are going to be able to systematically test out the utility of these individual enzymes.

There is also evolutionary work by other groups on the evolution of these Hypocreales fungi trying to better define when biotrophic and heterotrophic transitions occurred to sample fungi with different lifestyles that might have different cellulase enyzmes that may not have been observed. Defining the relationships of these fungi and when and how many times transitions to lifestyles occurred to choose the most diverse fungi may be an important part of discovering novel enzymes.

Also see

Martinez, D., Berka, R.M., Henrissat, B., Saloheimo, M., Arvas, M., Baker, S.E., Chapman, J., Chertkov, O., Coutinho, P.M., Cullen, D., Danchin, E.G., Grigoriev, I.V., Harris, P., Jackson, M., Kubicek, C.P., Han, C.S., Ho, I., Larrondo, L.F., de Leon, A.L., Magnuson, J.K., Merino, S., Misra, M., Nelson, B., Putnam, N., Robbertse, B., Salamov, A.A., Schmoll, M., Terry, A., Thayer, N., Westerholm-Parvinen, A., Schoch, C.L., Yao, J., Barbote, R., Nelson, M.A., Detter, C., Bruce, D., Kuske, C.R., Xie, G., Richardson, P., Rokhsar, D.S., Lucas, S.M., Rubin, E.M., Dunn-Coleman, N., Ward, M., Brettin, T.S. (2008). Genome sequencing and analysis of the biomass-degrading fungus Trichoderma reesei (syn. Hypocrea jecorina). Nature Biotechnology DOI: 10.1038/nbt1403