Webb, C.J., Zakian, V.A. (2008). Identification and characterization of the Schizosaccharomyces pombe TER1 telomerase RNA. Nature Structural & Molecular Biology, 15(1), 34-42. DOI: 10.1038/nsmb1354
Leonardi, J., Box, J.A., Bunch, J.T., Baumann, P. (2008). TER1, the RNA subunit of fission yeast telomerase. Nature Structural & Molecular Biology, 15(1), 26-33. DOI: 10.1038/nsmb1343
Two papers in Nature Structural & Molecular Biology identify the telomerase RNA in Schizosaccharomyces pombe. Telomerase is a multi-unit enzyme that has both protein and RNA components. While the protein subunit is highly conserved and identifiable through sequence comparisons of eukaryotes, the RNA subunit has a variable size and sequence making identification through comparative means more difficult. The S. pombe telomerase RNA subunit, or TER1, was discovered by two labs applying similar biochemical approaches to identify the locus.
Continue reading S.pombe telomerase RNA identified
Few organisms are as well understood at the genetic level as Saccharomyces cerevisiae. Given that there are more yeast geneticists than yeast genes and exemplary resources for the community (largely a result of their size), this comes as no surprise. What is curious is the large number of yeast genes for which we’ve been unable to characterize. Of the ~6000 genes currently identified in the yeast genome, 1253 have no verified function (for the uninclined, this is roughly 21% of the yeast proteome). Egads! If we can’t figure this out in yeast, what hope do we have in non-model organisms?Lourdes Peña-Castillo and Timothy R. Hughes discuss this curious observation and its cause in their report in Genetics.
Continue reading Yes, Ecology can improve Genomics
Ignazio Carbone and colleagues published a recent analysis of the evolution of the aflatoxin gene cluster in five Aspergillus fungi entitled “Gene duplication, modularity and adaptation in the evolution of the aflatoxin gene cluster” in BMC Evolutionary Biology. The authors were able to identify seven modules pairs of genes whose history of duplication were highly correlated. Several genomes of Aspergillus have been sequenced along with more Eurotioales fungi. Continue reading Evolution of aflatoxin gene cluster
A paper in PLoS One, Assessing Performance of Orthology Detection Strategies Applied to Eukaryotic Genomes, reports a new approach to assess the performance of automated orthology detection. These authors also wrote the OrthoMCL (2006 DB paper, 2003 algorithm paper) which uses MCL to build orthologous gene families. The authors discuss the trade-offs between highly
sensitive specific tree-based methods and fast but less sensitive approaches of the Best-Reciprocal-Hits from BLAST or FASTA or some of the hybrid approaches. The authors employ Latent Class Analysis (LCA) to aid in “evaluation and optimization of a comprehensive set of orthology detection methods, providing a guide for selecting methods and appropriate parameters”. LCA is also the statistical basis for feature choice in combing gene predictions into a single set of gene calls in GLEAN written by many of the same authors including Aaron Mackey.
I’ve been reading a lot of orthology and gene tree-species tree reconcilation papers lately, some are listed in Ian Holmes’s group as well as listing some of the software on the BioPerl site. This also follows with on our Phyloinformatics hackathon work which we are trying to formalize in some more documentation for phyloinformatics pipelines to support some of the described use cases. I’m also applying some of this to a tutorial I’m teaching at ISMB2007 this summer.
Steven Salzberg (who is nominated for the Franklin award at bioinformatics.org) has an opinion piece in Genome Biology proposing wiki technology to help solve the problem of genome annotations getting out of date.
Continue reading Wikis for genome (re)annotation