Last updated: 2025-06-27

Checks: 7 0

Knit directory: muse/

This reproducible R Markdown analysis was created with workflowr (version 1.7.1). The Checks tab describes the reproducibility checks that were applied when the results were created. The Past versions tab lists the development history.


Great! Since the R Markdown file has been committed to the Git repository, you know the exact version of the code that produced these results.

Great job! The global environment was empty. Objects defined in the global environment can affect the analysis in your R Markdown file in unknown ways. For reproduciblity it’s best to always run the code in an empty environment.

The command set.seed(20200712) was run prior to running the code in the R Markdown file. Setting a seed ensures that any results that rely on randomness, e.g. subsampling or permutations, are reproducible.

Great job! Recording the operating system, R version, and package versions is critical for reproducibility.

Nice! There were no cached chunks for this analysis, so you can be confident that you successfully produced the results during this run.

Great job! Using relative paths to the files within your workflowr project makes it easier to run your code on other machines.

Great! You are using Git for version control. Tracking code development and connecting the code version to the results is critical for reproducibility.

The results in this page were generated with repository version dfb1ef2. See the Past versions tab to see a history of the changes made to the R Markdown and HTML files.

Note that you need to be careful to ensure that all relevant files for the analysis have been committed to Git prior to generating the results (you can use wflow_publish or wflow_git_commit). workflowr only checks the R Markdown file, but you know if there are other scripts or data files that it depends on. Below is the status of the Git repository when the results were generated:


Ignored files:
    Ignored:    .Rproj.user/
    Ignored:    data/1M_neurons_filtered_gene_bc_matrices_h5.h5
    Ignored:    data/293t/
    Ignored:    data/293t_3t3_filtered_gene_bc_matrices.tar.gz
    Ignored:    data/293t_filtered_gene_bc_matrices.tar.gz
    Ignored:    data/5k_Human_Donor1_PBMC_3p_gem-x_5k_Human_Donor1_PBMC_3p_gem-x_count_sample_filtered_feature_bc_matrix.h5
    Ignored:    data/5k_Human_Donor2_PBMC_3p_gem-x_5k_Human_Donor2_PBMC_3p_gem-x_count_sample_filtered_feature_bc_matrix.h5
    Ignored:    data/5k_Human_Donor3_PBMC_3p_gem-x_5k_Human_Donor3_PBMC_3p_gem-x_count_sample_filtered_feature_bc_matrix.h5
    Ignored:    data/5k_Human_Donor4_PBMC_3p_gem-x_5k_Human_Donor4_PBMC_3p_gem-x_count_sample_filtered_feature_bc_matrix.h5
    Ignored:    data/97516b79-8d08-46a6-b329-5d0a25b0be98.h5ad
    Ignored:    data/Parent_SC3v3_Human_Glioblastoma_filtered_feature_bc_matrix.tar.gz
    Ignored:    data/brain_counts/
    Ignored:    data/cl.obo
    Ignored:    data/cl.owl
    Ignored:    data/jurkat/
    Ignored:    data/jurkat:293t_50:50_filtered_gene_bc_matrices.tar.gz
    Ignored:    data/jurkat_293t/
    Ignored:    data/jurkat_filtered_gene_bc_matrices.tar.gz
    Ignored:    data/pbmc20k/
    Ignored:    data/pbmc20k_seurat/
    Ignored:    data/pbmc3k.h5ad
    Ignored:    data/pbmc3k/
    Ignored:    data/pbmc3k_bpcells_mat/
    Ignored:    data/pbmc3k_export.mtx
    Ignored:    data/pbmc3k_matrix.mtx
    Ignored:    data/pbmc3k_seurat.rds
    Ignored:    data/pbmc4k_filtered_gene_bc_matrices.tar.gz
    Ignored:    data/pbmc_1k_v3_filtered_feature_bc_matrix.h5
    Ignored:    data/pbmc_1k_v3_raw_feature_bc_matrix.h5
    Ignored:    data/refdata-gex-GRCh38-2020-A.tar.gz
    Ignored:    data/seurat_1m_neuron.rds
    Ignored:    data/t_3k_filtered_gene_bc_matrices.tar.gz
    Ignored:    r_packages_4.4.1/
    Ignored:    r_packages_4.5.0/

Untracked files:
    Untracked:  Caenorhabditis_elegans.WBcel235.113.gtf.gz
    Untracked:  Nothobranchius_furzeri.Nfu_20140520.113.gtf.gz
    Untracked:  analysis/bioc_scrnaseq.Rmd
    Untracked:  bpcells_matrix/
    Untracked:  data/Caenorhabditis_elegans.WBcel235.113.gtf.gz
    Untracked:  data/GCF_043380555.1-RS_2024_12_gene_ontology.gaf.gz
    Untracked:  data/celegans_gene_id_to_go_id.csv.gz
    Untracked:  data/celegans_gene_info.csv.gz
    Untracked:  m3/
    Untracked:  pbmc3k_before_filtering.rds
    Untracked:  pbmc3k_save_rds.rds
    Untracked:  rsem.merged.gene_counts.tsv

Note that any generated files, e.g. HTML, png, CSS, etc., are not included in this status report because it is ok for generated content to have uncommitted changes.


These are the previous versions of the repository in which changes were made to the R Markdown (analysis/celegans.Rmd) and HTML (docs/celegans.html) files. If you’ve configured a remote Git repository (see ?wflow_git_remote), click on the hyperlinks in the table below to view the files as they were in that past version.

File Version Author Date Message
Rmd dfb1ef2 Dave Tang 2025-06-27 Caenorhabditis elegans

The biomaRt package provides an interface to BioMart databases provided by Ensembl.

biomaRt provides an interface to a growing collection of databases implementing the BioMart software suite. The package enables retrieval of large amounts of data in a uniform way without the need to know the underlying database schemas or write complex SQL queries. The most prominent examples of BioMart databases are maintain by Ensembl, which provides biomaRt users direct access to a diverse set of data and enables a wide range of powerful online queries from gene annotation to database mining.

For more information, check out the Accessing Ensembl annotation with biomaRt guide.

Installation

To begin, install the {biomaRt} package.

if (!require("BiocManager", quietly = TRUE))
    install.packages("BiocManager")

BiocManager::install("biomaRt")

Package

Load package.

packageVersion("biomaRt")
[1] '2.64.0'
suppressPackageStartupMessages(library(biomaRt))

Getting started

Use mirror.

ensembl <- useEnsembl(biomart = "ensembl", mirror = "asia")
ensembl
Object of class 'Mart':
  Using the ENSEMBL_MART_ENSEMBL BioMart database
  No dataset selected.

Connect to the selected BioMart database by using useMart().

avail_datasets <- listDatasets(ensembl)
head(avail_datasets)
                       dataset                           description
1 abrachyrhynchus_gene_ensembl Pink-footed goose genes (ASM259213v1)
2     acalliptera_gene_ensembl      Eastern happy genes (fAstCal1.3)
3   acarolinensis_gene_ensembl       Green anole genes (AnoCar2.0v2)
4    acchrysaetos_gene_ensembl       Golden eagle genes (bAquChr1.2)
5    acitrinellus_gene_ensembl        Midas cichlid genes (Midas_v5)
6    amelanoleuca_gene_ensembl       Giant panda genes (ASM200744v2)
      version
1 ASM259213v1
2  fAstCal1.3
3 AnoCar2.0v2
4  bAquChr1.2
5    Midas_v5
6 ASM200744v2

Look for C. elegans datasets by searching the description column.

idx <- grep(pattern = "elegans", avail_datasets$dataset, ignore.case = TRUE)
avail_datasets[idx, ]
                 dataset                                            description
27 celegans_gene_ensembl Caenorhabditis elegans (Nematode, N2) genes (WBcel235)
    version
27 WBcel235

Connect to the selected BioMart database and Caenorhabditis elegans dataset.

ensembl <- useEnsembl(biomart = "ensembl", mirror = "asia", dataset=avail_datasets[idx, 'dataset'])
ensembl
Object of class 'Mart':
  Using the ENSEMBL_MART_ENSEMBL BioMart database
  Using the celegans_gene_ensembl dataset

Building a query, requires three things:

  1. filters
  2. attributes
  3. values

Use listFilters() to show available filters.

avail_filters <- listFilters(ensembl)
head(avail_filters)
                name
1    chromosome_name
2              start
3                end
4             strand
5 chromosomal_region
6       with_biogrid
                                                                           description
1                                                             Chromosome/scaffold name
2                                                                                Start
3                                                                                  End
4                                                                               Strand
5                                               e.g. 1:100:10000:-1, 1:100000:200000:1
6 With BioGRID Interaction data, The General Repository for Interaction Datasets ID(s)

Use listAttributes() to show available attributes.

avail_attributes <- listAttributes(ensembl)
avail_attributes |>
  head()
                   name              description         page
1       ensembl_gene_id           Gene stable ID feature_page
2 ensembl_transcript_id     Transcript stable ID feature_page
3    ensembl_peptide_id        Protein stable ID feature_page
4       ensembl_exon_id           Exon stable ID feature_page
5           description         Gene description feature_page
6       chromosome_name Chromosome/scaffold name feature_page

The getBM() function is the main query function in {biomaRt}; use it once you have identified your attributes of interest and filters to use. Note that the gene IDs aren’t really Ensembl Gene IDs.

gene_ids <- c("WBGene00000007", "WBGene00000027", "WBGene00000056", "WBGene00000071")

getBM(
  attributes=c('ensembl_gene_id', 'external_gene_name', 'description'),
  filters = 'ensembl_gene_id',
  values = gene_ids,
  mart = ensembl
) -> res

res
  ensembl_gene_id external_gene_name
1  WBGene00000007              aat-6
2  WBGene00000027              abu-4
3  WBGene00000056             acr-17
4  WBGene00000071              acy-4
                                                                                                          description
1                                Amino acid transporter protein 6 [Source:NCBI gene (formerly Entrezgene);Acc:188421]
2                  Activated in Blocked Unfolded protein response [Source:NCBI gene (formerly Entrezgene);Acc:353458]
3 AcetylCholine Receptor;Neur_chan_memb domain-containing protein [Source:NCBI gene (formerly Entrezgene);Acc:191603]
4                                               adenylate cyclase [Source:NCBI gene (formerly Entrezgene);Acc:178949]

All gene IDs.

gtf_file <- "https://ftp.ensembl.org/pub/release-113/gtf/caenorhabditis_elegans/Caenorhabditis_elegans.WBcel235.113.gtf.gz"
if(file.exists(basename(gtf_file)) == FALSE){
  download.file(url = gtf_file, destfile = basename(gtf_file))
}

gtf_cols <- c(
  "seqname",
  "source",
  "feature",
  "start",
  "end",
  "score",
  "strand",
  "frame",
  "attribute"
)

gtf <- readr::read_tsv(file = gtf_file, comment = "#", col_names = gtf_cols, show_col_types = FALSE)
gtf |>
  dplyr::filter(feature == "gene") |>
  dplyr::select(attribute) |>
  tidyr::separate_rows(attribute, sep = ";\\s*") |>
  dplyr::filter(grepl("gene_id", attribute)) |>
  tidyr::separate(attribute, c('key', 'value'), sep = "\\s") |>
  dplyr::pull(value) |>
  gsub(pattern ='"', replacement = "") -> all_gene_ids

length(all_gene_ids) == length(unique(all_gene_ids))
[1] TRUE

Get gene names and descriptions.

getBM(
  attributes=c('ensembl_gene_id', 'external_gene_name', 'description'),
  filters = 'ensembl_gene_id',
  values = all_gene_ids,
  mart = ensembl
) -> all_gene_info

head(all_gene_info)
  ensembl_gene_id external_gene_name
1  WBGene00000003              aat-2
2  WBGene00000007              aat-6
3  WBGene00000014              abf-3
4  WBGene00000015              abf-4
5  WBGene00000022              abt-4
6  WBGene00000024              abu-1
                                                                                         description
1                         Amino Acid Transporter [Source:NCBI gene (formerly Entrezgene);Acc:184126]
2               Amino acid transporter protein 6 [Source:NCBI gene (formerly Entrezgene);Acc:188421]
3                   AntiBacterial Factor related [Source:NCBI gene (formerly Entrezgene);Acc:186202]
4                   AntiBacterial Factor related [Source:NCBI gene (formerly Entrezgene);Acc:189702]
5      ABC transporter domain-containing protein [Source:NCBI gene (formerly Entrezgene);Acc:178559]
6 Activated in Blocked Unfolded protein response [Source:NCBI gene (formerly Entrezgene);Acc:181800]

Save lookup table.

readr::write_csv(x = all_gene_info, file = "data/celegans_gene_info.csv.gz")

Gene Ontology terms

Find GO attribute names.

grep("^go", avail_attributes$name, ignore.case=TRUE, value=TRUE)
[1] "go_id"                  "go_linkage_type"        "goslim_goa_accession"  
[4] "goslim_goa_description"

Query.

getBM(
  attributes=c("ensembl_gene_id", "go_id"),
  filters="ensembl_gene_id",
  values = all_gene_ids,
  mart = ensembl
) -> all_gene_go_ids

head(all_gene_go_ids)
  ensembl_gene_id      go_id
1  WBGene00000003 GO:0016020
2  WBGene00000003 GO:0055085
3  WBGene00000003 GO:0022857
4  WBGene00000003 GO:0003333
5  WBGene00000003 GO:1902475
6  WBGene00000003 GO:0015179

Save GO table.

readr::write_csv(x = all_gene_go_ids, file = "data/celegans_gene_id_to_go_id.csv.gz")

sessionInfo()
R version 4.5.0 (2025-04-11)
Platform: x86_64-pc-linux-gnu
Running under: Ubuntu 24.04.2 LTS

Matrix products: default
BLAS:   /usr/lib/x86_64-linux-gnu/openblas-pthread/libblas.so.3 
LAPACK: /usr/lib/x86_64-linux-gnu/openblas-pthread/libopenblasp-r0.3.26.so;  LAPACK version 3.12.0

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
 [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
 [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
 [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       

time zone: Etc/UTC
tzcode source: system (glibc)

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] biomaRt_2.64.0  workflowr_1.7.1

loaded via a namespace (and not attached):
 [1] KEGGREST_1.48.1         xfun_0.52               bslib_0.9.0            
 [4] httr2_1.1.2             processx_3.8.6          Biobase_2.68.0         
 [7] tzdb_0.5.0              callr_3.7.6             vctrs_0.6.5            
[10] tools_4.5.0             ps_1.9.1                generics_0.1.4         
[13] parallel_4.5.0          curl_6.4.0              stats4_4.5.0           
[16] tibble_3.3.0            AnnotationDbi_1.70.0    RSQLite_2.4.1          
[19] blob_1.2.4              pkgconfig_2.0.3         dbplyr_2.5.0           
[22] S4Vectors_0.46.0        lifecycle_1.0.4         GenomeInfoDbData_1.2.14
[25] compiler_4.5.0          stringr_1.5.1           git2r_0.36.2           
[28] Biostrings_2.76.0       progress_1.2.3          getPass_0.2-4          
[31] httpuv_1.6.16           GenomeInfoDb_1.44.0     htmltools_0.5.8.1      
[34] sass_0.4.10             yaml_2.3.10             tidyr_1.3.1            
[37] later_1.4.2             pillar_1.10.2           crayon_1.5.3           
[40] jquerylib_0.1.4         whisker_0.4.1           cachem_1.1.0           
[43] tidyselect_1.2.1        digest_0.6.37           stringi_1.8.7          
[46] purrr_1.0.4             dplyr_1.1.4             rprojroot_2.0.4        
[49] fastmap_1.2.0           cli_3.6.5               magrittr_2.0.3         
[52] readr_2.1.5             withr_3.0.2             filelock_1.0.3         
[55] prettyunits_1.2.0       UCSC.utils_1.4.0        promises_1.3.3         
[58] rappdirs_0.3.3          bit64_4.6.0-1           rmarkdown_2.29         
[61] XVector_0.48.0          httr_1.4.7              bit_4.6.0              
[64] png_0.1-8               hms_1.1.3               memoise_2.0.1          
[67] evaluate_1.0.4          knitr_1.50              IRanges_2.42.0         
[70] BiocFileCache_2.16.0    rlang_1.1.6             Rcpp_1.0.14            
[73] glue_1.8.0              DBI_1.2.3               xml2_1.3.8             
[76] BiocGenerics_0.54.0     vroom_1.6.5             rstudioapi_0.17.1      
[79] jsonlite_2.0.0          R6_2.6.1                fs_1.6.6