ENCODExplorer: A compilation of metadata from ENCODE ==================================================================== Audrey Lemacon, Louis Gendron Charles Joly Beauparlant and Arnaud Droit. This package and the underlying ENCODExplorer code are distributed under the Artistic license 2.0. You are free to use and redistribute this software. "The ENCODE (Encyclopedia of DNA Elements) Consortium is an international collaboration of research groups funded by the National Human Genome Research Institute (NHGRI). The goal of ENCODE is to build a comprehensive parts list of functional elements in the human genome, including elements that act at the protein and RNA levels, and regulatory elements that control cells and circumstances in which a gene is active"^[source : [ENCODE Projet Portal ](https://www.encodeproject.org/)]. However, data retrieval and downloading can be really time-consuming using the current web portal. This package has been designed to facilitate data access by compiling the metadata associated with file, experiment and dataset. We first extract ENCODE schema from its public github repository. Then we identify the main entities and their relationship with each other to rebuild the ENCODE database into an SQLite database. We also developped a function which can extract the essential metadata in a R object to aid data exploration. We implemented time-saving features to select ENCODE files by querying their metadata and download them. The SQLite database can be regenerated at will to query ENCODE database locally keep it up-to-date. This vignette will introduce the imputed ENCODE database model. ### Loading ENCODExplorer package ```{r libraryLoad} suppressMessages(library(ENCODExplorer)) ``` ### Data preparation To generate the list of data.table from ENCODE: ```{r tables, eval=FALSE} # the path (relative or absolute) to the future database database_filename = "encode.dt" tables = prepare_ENCODEdb(database_filename) ``` The process can take a few minutes. ### Schema  The edges indicate relationship between two tables : an origin and a destination. The relation is made between a column of the origin table and the *id* of the destination table. Those relations are described in the following table: ### Relations table |origin| destination|origin column| |---------|------------|-------------| |access_key|user|user| |analysis_step|analysis_step|parents| |analysis_step|document|documents| |analysis_step_run|analysis_step|analysis_step| |analysis_step_run|workflow_run|workflow_run| |analysis_step|software_version|software_versions| |antibody_approval|antibody_characterization|characterizations| |antibody_approval|antibody_lot|antibody| |antibody_approval|target|target| |antibody_characterization|antibody_lot|characterizes| |antibody_characterization|target|target| |antibody_characterization|user|reviewed_by| |antibody_lot|organism|host_organism| |antibody_lot|target|targets| |award|user|pi| |biosample|biosample|derived_from| |biosample|biosample|part_of| |biosample|biosample|pooled_from| |biosample_characterization|biosample|characterizes| |biosample|construct|constructs| |biosample|document|protocol_documents| |biosample|donor|donor| |biosample|organism|organism| |biosample|rnai|rnais| |biosample|talen|talens| |biosample|treatment|treatments| |characterization|document|documents| |construct_characterization|construct|characterizes| |construct|document|documents| |construct|target|promoter_used| |construct|target|target| |dataset|document|documents| |dataset|file|related_files| |donor_characterization|donor|characterizes| |donor|organism|organism| |experiment|experiment|possible_controls| |experiment|target|target| |file|analysis_step_run|step_run| |file|dataset|dataset| |file|experiment|dataset| |file|file|controlled_by| |file|file|derived_from| |file|file|paired_with| |file|file|supercedes| |file|platform|platform| |file|replicate|replicate| |fly_donor|document|documents| |human_donor|human_donor|children| |human_donor|human_donor|fraternal_twin| |human_donor|human_donor|identical_twin| |human_donor|human_donor|parents| |human_donor|human_donor|siblings| |lab|award|awards| |lab|user|pi| |library|biosample|biosample| |library|dataset|spikeins_used| |library|document|documents| |library|treatment|treatments| |mouse_donor|mouse_donor|littermates| |page|page|parent| |pipeline|analysis_step|analysis_steps| |pipeline|analysis_step|end_points| |pipeline|document|documents| |publication|dataset|datasets| |quality_metric|analysis_step_run|step_run| |quality_metric|file|files| |replicate|antibody_lot|antibody| |replicate|experiment|experiment| |replicate|library|library| |replicate|platform|platform| |rnai_characterization|rnai|characterizes| |rnai|document|documents| |rnai|target|target| |software|publication|references| |software_version|software|software| |talen|document|documents| |target|organism|organism| |treatment|document|protocols| |treatment|lab|lab| |user|lab|lab| |user|lab|submits_for| |workflow_run|file|input_files| |workflow_run|pipeline|pipeline| |workflow_run|software_version|software_version| |worm_donor|document|documents| |worm_donor|worm_donor|outcrossed_strain| For example: [**file** ---> **replicate** ---> *replicate*] enables to write the following relation : **file**.*replicate* = **replicate**.*id*.