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Rokhsar, Dan

Publications and source records attributed to Rokhsar, Dan.

JGI Plant Genomics Gene Annotation Pipeline

Plant genomes vary in size and are highly complex with a high amount of repeats, genome duplication and tandem duplication. Gene encodes a wealth of information useful in studying organism and it is critical to have high quality and stable gene annotation. Thanks to advancement of sequencing technology, many plant species genomes have been sequenced and transcriptomes are also sequenced. To use these vastly large amounts of sequence data to make gene annotation or re-annotation in a timely fashion, an automatic pipeline is needed. JGI plant genomics gene annotation pipeline, called integrated gene call (IGC), is our effort toward this aim with aid of a RNA-seq transcriptome assembly pipeline. It utilizes several gene predictors based on homolog peptides and transcript ORFs. See Methods for detail. Here we present genome annotation of JGI flagship green plants produced by this pipeline plus Arabidopsis and rice except for chlamy which is done by a third party. The genome annotations of these species and others are used in our gene family build pipeline and accessible via JGI Phytozome portal whose URL and front page snapshot are shown below.

99 GENERAL AND MISCELLANEOUS↗

InterMine Webservices for Phytozome (Rev2)

A datawarehousing framework for information provides a useful infrastructure for providers and users of genomic data. For providers, the infrastructure give them a consistent mechanism for extracting raw data. While for the users, the web services supported by the software allows them to make complex, and often unique, queries of the data. Previously, phytozome.net used BioMart to provide the infrastructure. As the complexity, scale and diversity of the dataset as grown, we decided to implement an InterMine web service on our servers. This change was largely motivated by the ability to have a more complex table structure and richer web reporting mechanism than BioMart. For InterMine to achieve its more complex database schema it requires an XML description of the data and an appropriate loader. Unlimited one-to-many and many-to-many relationship between the tables can be enabled in the schema. We have implemented support for:1.) Genomes and annotations for the data in Phytozome. This set is the 48 organisms currently stored in a back end CHADO datastore. The data loaders are modified versions of the CHADO data adapters from FlyMine. 2.) Interproscan results from all proteins in the Phytozome database. 3.) Clusters of proteins into a grouped heirarchically by similarity. 4.) Cufflinks results from tissue-specific RNA-Seq data of Phytozome organisms. 5.) Diversity data (GATK and SnpEFF results) from a set of individual organism. The last two datatypes are new in this implementation of our web services. We anticipate that the scale of these data will increase considerably in the near future.

99 GENERAL AND MISCELLANEOUS↗

PERTRAN: Genome-guided RNA-seq Read Assembler

As short RNA-seq reads become a standard, affordable input to any genome annotation project, a sensitive and accurate transcript assembler is an essential part of any gene prediction system. PERTRAN is a pipeline for assembling transcripts from RNA-seq reads which demonstrates higher sensitivity, with fewer fused exons (in most cases), and faster run times compared to other TOPHAT/CUFFLINKS and genome-guided Trinity. PERTRAN shows slightly lower specificity with increased gene fusions in some cases, discussed below. SAM files generated from PERTRAN can be used to compute expression level by cuffdiff and result is comparable to that from TOPHAT.

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