PaperBLAST – Find papers about a protein or its homologs

 

PaperBLAST

PaperBLAST Hits for TCDB::A4HUI4 Proline/alanine transporter of 488 aas and 10 TMSs, AAP24. The first 18 amino acids of the negatively charged N-terminal LdAAP24 tail are required for alanine transport and may facilitate the electrostatic interactions of the entire negatively charged N-terminal tail with the positively charged internal loops in the transmembrane domain (Leishmania infantum) (488 a.a., MSRLPSTASD...)

Other sequence analysis tools:

Find functional residues: SitesBLAST

Search for conserved domains

Find the best match in UniProt

Compare to protein structures

Predict transmenbrane helices: Phobius

Predict protein localization: PSORTb

Find homologs in fast.genomics

Fitness BLAST: loading...

Found 44 similar proteins in the literature:

TC 2.A.18.7.4 / A4HUI4 Proline/alanine transporter of 488 aas and 10 TMSs, AAP24. The first 18 amino acids of the negatively charged N-terminal LdAAP24 tail are required for alanine transport and may facilitate the electrostatic interactions of the entire negatively charged N-terminal tail with the positively charged internal loops in the transmembrane domain from Leishmania infantum
100% identity, 100% coverage

AVT3_SCHPO / Q10074 Vacuolar amino acid transporter 3 from Schizosaccharomyces pombe (strain 972 / ATCC 24843) (Fission yeast) (see 2 papers)
TC 2.A.18.7.3 / Q10074 Vacuolar amino acid transporter 3, Avt3 from Schizosaccharomyces pombe (strain 972 / ATCC 24843) (see 4 papers)
avt3 vacuolar amino acid efflux transporter Avt3 from Schizosaccharomyces pombe (see 2 papers)
NP_593551 vacuolar amino acid transmembrane transporter Avt3 from Schizosaccharomyces pombe
23% identity, 53% coverage

CG16700 uncharacterized protein from Drosophila melanogaster
23% identity, 81% coverage

PGUG_00636 uncharacterized protein from Meyerozyma guilliermondii ATCC 6260
22% identity, 78% coverage

S36A4_HUMAN / Q6YBV0 Neutral amino acid uniporter 4; Solute carrier family 36 member 4 from Homo sapiens (Human) (see 2 papers)
TC 2.A.18.8.5 / Q6YBV0 H+-coupled amino acid transporter-4; SLC36A4 from Homo sapiens (see 3 papers)
NP_689526 neutral amino acid uniporter 4 isoform 1 from Homo sapiens
22% identity, 82% coverage

AVT3B_ARATH / F4ILY9 Amino acid transporter AVT3B; AtAvt3B; Aromatic and neutral amino acid transporter-like protein 1 from Arabidopsis thaliana (Mouse-ear cress) (see paper)
AT2G42005 amino acid transporter family protein from Arabidopsis thaliana
NP_850361 Transmembrane amino acid transporter family protein from Arabidopsis thaliana
24% identity, 73% coverage

LOC101745823 proton-coupled amino acid transporter-like protein pathetic from Bombyx mori
21% identity, 77% coverage

S36A1_MOUSE / Q8K4D3 Proton-coupled amino acid transporter 1; Proton/amino acid transporter 1; Solute carrier family 36 member 1 from Mus musculus (Mouse) (see paper)
TC 2.A.18.8.1 / Q8K4D3 The electrogenic, proton-dependent amino acid:H+ symporter, PAT1 or LYAAT-1 (Slc36A1). Catalyzes uptake of L-Gly, L-Ala, L-Pro, γ-amino butyrate, and short chain D-amino acids such as proline and hydroxyproline with an aa/ H+ ratio of 1:1 (found in lysosomes) In humans, this is the iminoglycinuria protein (Boll et al., 2004; from Mus musculus (Mouse) (see 2 papers)
Slc36a1 / RF|NP_694779.3 proton-coupled amino acid transporter 1 from Mus musculus (see paper)
NP_694779 proton-coupled amino acid transporter 1 from Mus musculus
23% identity, 85% coverage

S36A1_RAT / Q924A5 Proton-coupled amino acid transporter 1; Proton/amino acid transporter 1; Lysosomal amino acid transporter 1; LYAAT-1; Neutral amino acid/proton symporter; Solute carrier family 36 member 1 from Rattus norvegicus (Rat) (see 2 papers)
XP_008765881 proton-coupled amino acid transporter 1 isoform X1 from Rattus norvegicus
22% identity, 85% coverage

S36A1_HUMAN / Q7Z2H8 Proton-coupled amino acid transporter 1; Proton/amino acid transporter 1; hPAT1; Solute carrier family 36 member 1 from Homo sapiens (Human) (see 4 papers)
TC 2.A.18.8.7 / Q7Z2H8 Proton-coupled amino acid transporter 1 (Proton/amino acid transporter 1) (hPAT1 or LYAAT-1) (Solute carrier family 36 member 1) from Homo sapiens (see 6 papers)
XP_011535893 proton-coupled amino acid transporter 1 isoform X3 from Homo sapiens
22% identity, 85% coverage

TGME49_227570 transmembrane amino acid transporter protein from Toxoplasma gondii ME49
22% identity, 81% coverage

S36A4_MOUSE / Q8CH36 Neutral amino acid uniporter 4; Solute carrier family 36 member 4 from Mus musculus (Mouse) (see paper)
22% identity, 75% coverage

S36A3_MOUSE / Q811P0 Proton-coupled amino acid transporter 3; Proton/amino acid transporter 3; Solute carrier family 36 member 3; Tramdorin-2 from Mus musculus (Mouse) (see 2 papers)
23% identity, 70% coverage

XP_011247200 proton-coupled amino acid transporter 3 isoform X2 from Mus musculus
23% identity, 70% coverage

XP_005667282 proton-coupled amino acid transporter 4 isoform X1 from Sus scrofa
21% identity, 74% coverage

AVT3A_ARATH / Q9FKY3 Amino acid transporter AVT3A; AtAvt3A; Aromatic and neutral amino acid transporter-like protein 3 from Arabidopsis thaliana (Mouse-ear cress) (see paper)
AT5G65990 amino acid transporter family protein from Arabidopsis thaliana
NP_201400 Transmembrane amino acid transporter family protein from Arabidopsis thaliana
25% identity, 60% coverage

S36A_DROME / Q9W056 Proton-coupled amino acid transporter-like protein acs; Protein arcus from Drosophila melanogaster (Fruit fly) (see 3 papers)
NP_647686 arcus from Drosophila melanogaster
25% identity, 76% coverage

S36A3_HUMAN / Q495N2 Proton-coupled amino acid transporter 3; Proton/amino acid transporter 3; Solute carrier family 36 member 3; Tramdorin-2 from Homo sapiens (Human) (see paper)
TC 2.A.18.8.4 / Q495N2 H+-coupled amino acid transporter-3 (SLC36A3) from Homo sapiens (see 5 papers)
NP_861439 proton-coupled amino acid transporter 3 isoform 2 from Homo sapiens
23% identity, 74% coverage

AVT3C_ARATH / Q9SVG0 Amino acid transporter AVT3C; AtAvt3C; Aromatic and neutral amino acid transporter-like protein 2 from Arabidopsis thaliana (Mouse-ear cress) (see paper)
NP_195538 Transmembrane amino acid transporter family protein from Arabidopsis thaliana
AT4G38250 amino acid transporter family protein from Arabidopsis thaliana
25% identity, 71% coverage

AVT3_YEAST / P36062 Vacuolar amino acid transporter 3 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast) (see paper)
TC 2.A.18.7.1 / P36062 The vacuolar amino acid transporter, AVT3 (catalyzes efflux from yeast vacuoles of large neutral amino acids such as tyr, gln, asn, leu and ile) (see 6 papers)
AVT3 / RF|NP_012776.1 vacuolar amino acid transporter 3 from Saccharomyces cerevisiae
YKL146W Avt3p from Saccharomyces cerevisiae
21% identity, 53% coverage

FOXG_11334 hypothetical protein from Fusarium oxysporum f. sp. lycopersici 4287
20% identity, 73% coverage

AVT4_YEAST / P50944 Vacuolar amino acid transporter 4 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast) (see paper)
TC 2.A.18.7.2 / P50944 Vacuolar amino acid transporter 4 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (see 6 papers)
NP_014298 Avt4p from Saccharomyces cerevisiae S288C
YNL101W Avt4p from Saccharomyces cerevisiae
23% identity, 43% coverage

S36A2_HUMAN / Q495M3 Proton-coupled amino acid transporter 2; Proton/amino acid transporter 2; Solute carrier family 36 member 2; Transmembrane domain rich protein 1; Tramdorin-1 from Homo sapiens (Human) (see 3 papers)
TC 2.A.18.8.6 / Q495M3 Proton-coupled amino acid transporter 2 (Proton/amino acid transporter 2) (Solute carrier family 36 member 2) (Tramdorin-1) from Homo sapiens (see 5 papers)
NP_861441 proton-coupled amino acid transporter 2 from Homo sapiens
20% identity, 83% coverage

LOC105049578 amino acid transporter ANT1-like from Elaeis guineensis
24% identity, 69% coverage

NCU05775 amino acid transporter from Neurospora crassa OR74A
20% identity, 55% coverage

NCU03783 transmembrane domain transporter from Neurospora crassa OR74A
21% identity, 44% coverage

NP_647555 proton-coupled amino acid transporter 2 from Rattus norvegicus
21% identity, 58% coverage

S36A2_MOUSE / Q8BHK3 Proton-coupled amino acid transporter 2; Proton/amino acid transporter 2; Solute carrier family 36 member 2; Transmembrane domain rich protein 1; Tramdorin-1 from Mus musculus (Mouse) (see 5 papers)
TC 2.A.18.8.2 / Q8BHK3 Electrogenic, proton-coupled, amino acid symporter 2 (PAT2; Tramdorin-1; SLC36A2) (transports small amino acids: glycine, alanine and proline; found in the ER, not in lysosomes, of neuronal cells in the brain and spinal cord; it can catalyze bidirectional transport depending on the driving force) (Boll et al., 2004; from Mus musculus (Mouse) (see 9 papers)
Slc36a2 / RF|NP_694810.1 proton-coupled amino acid transporter 2 from Mus musculus (see paper)
NP_694810 proton-coupled amino acid transporter 2 from Mus musculus
20% identity, 58% coverage

LOC100168251 proton-coupled amino acid transporter-like protein CG1139 from Acyrthosiphon pisum
20% identity, 75% coverage

LOC100644921 proton-coupled amino acid transporter-like protein CG1139 from Bombus terrestris
22% identity, 65% coverage

S36A2_RAT / Q8K415 Proton-coupled amino acid transporter 2; Proton/amino acid transporter 2; rPAT2; Solute carrier family 36 member 2; Transmembrane domain rich protein 1; Tramdorin-1 from Rattus norvegicus (Rat) (see 2 papers)
22% identity, 71% coverage

LOC105841453 proton-coupled amino acid transporter 1 from Bombyx mori
20% identity, 72% coverage

LOC100642564 proton-coupled amino acid transporter-like protein pathetic from Bombus terrestris
21% identity, 58% coverage

ANT1_ARATH / Q9SF09 Amino acid transporter ANT1; Aromatic and neutral amino acid transporter 1 from Arabidopsis thaliana (Mouse-ear cress) (see 2 papers)
AT3G11900 ANT1 (AROMATIC AND NEUTRAL TRANSPORTER 1); amino acid transmembrane transporter/ aromatic amino acid transmembrane transporter/ neutral amino acid transmembrane transporter from Arabidopsis thaliana
21% identity, 65% coverage

PATH_DROME / Q9VT04 Proton-coupled amino acid transporter-like protein pathetic from Drosophila melanogaster (Fruit fly) (see 4 papers)
TC 2.A.18.8.3 / Q9VT04 Amino acid transporter (low capacity, high affinity) and amino acid-dependent signal transduction protein, Pathetic (Path) from Drosophila melanogaster (Fruit fly) (see 2 papers)
path / RF|NP_648327.1 RH24992p from Drosophila melanogaster (see paper)
NP_648327 pathetic, isoform A from Drosophila melanogaster
21% identity, 67% coverage

LOC113506931 proton-coupled amino acid transporter-like protein pathetic from Trichoplusia ni
22% identity, 80% coverage

cgd7_4800 ABC transporter, amino acid transporter 12 transmembrane spanning subunit from Cryptosporidium parvum Iowa II
21% identity, 45% coverage

J7RA72 Putative lysine/histidine transporter from Hordeum vulgare
22% identity, 72% coverage

TGME49_227580 transmembrane amino acid transporter protein from Toxoplasma gondii ME49
20% identity, 68% coverage

AT3G01760 lysine and histidine specific transporter, putative from Arabidopsis thaliana
20% identity, 72% coverage

LOC105051602 lysine histidine transporter 1 from Elaeis guineensis
20% identity, 69% coverage

LDBPK_071340 amino acid transporter, putative from Leishmania donovani
21% identity, 68% coverage

Q4DMS3 ABC-type polar-amino-acid transporter (EC 7.4.2.1) from Trypanosoma cruzi (see paper)
21% identity, 67% coverage

LHT1_ARATH / Q9FKS8 Lysine histidine transporter 1 from Arabidopsis thaliana (Mouse-ear cress) (see 4 papers)
TC 2.A.18.2.2 / Q9FKS8 Lysine/histidine transporter, LHT1 (see 8 papers)
NP_851109 lysine histidine transporter 1 from Arabidopsis thaliana
AT5G40780, NP_851109 LHT1; amino acid transmembrane transporter from Arabidopsis thaliana
20% identity, 79% coverage

New Search

For advice on how to use these tools together, see Interactive tools for functional annotation of bacterial genomes.

Statistics

The PaperBLAST database links 793,807 different protein sequences to 1,259,118 scientific articles. Searches against EuropePMC were last performed on March 13 2025.

How It Works

PaperBLAST builds a database of protein sequences that are linked to scientific articles. These links come from automated text searches against the articles in EuropePMC and from manually-curated information from GeneRIF, UniProtKB/Swiss-Prot, BRENDA, CAZy (as made available by dbCAN), BioLiP, CharProtDB, MetaCyc, EcoCyc, TCDB, REBASE, the Fitness Browser, and a subset of the European Nucleotide Archive with the /experiment tag. Given this database and a protein sequence query, PaperBLAST uses protein-protein BLAST to find similar sequences with E < 0.001.

To build the database, we query EuropePMC with locus tags, with RefSeq protein identifiers, and with UniProt accessions. We obtain the locus tags from RefSeq or from MicrobesOnline. We use queries of the form "locus_tag AND genus_name" to try to ensure that the paper is actually discussing that gene. Because EuropePMC indexes most recent biomedical papers, even if they are not open access, some of the links may be to papers that you cannot read or that our computers cannot read. We query each of these identifiers that appears in the open access part of EuropePMC, as well as every locus tag that appears in the 500 most-referenced genomes, so that a gene may appear in the PaperBLAST results even though none of the papers that mention it are open access. We also incorporate text-mined links from EuropePMC that link open access articles to UniProt or RefSeq identifiers. (This yields some additional links because EuropePMC uses different heuristics for their text mining than we do.)

For every article that mentions a locus tag, a RefSeq protein identifier, or a UniProt accession, we try to select one or two snippets of text that refer to the protein. If we cannot get access to the full text, we try to select a snippet from the abstract, but unfortunately, unique identifiers such as locus tags are rarely provided in abstracts.

PaperBLAST also incorporates manually-curated protein functions:

Except for GeneRIF and ENA, the curated entries include a short curated description of the protein's function. For entries from BioLiP, the protein's function may not be known beyond binding to the ligand. Many of these entries also link to articles in PubMed.

For more information see the PaperBLAST paper (mSystems 2017) or the code. You can download PaperBLAST's database here.

Changes to PaperBLAST since the paper was written:

Many of these changes are described in Interactive tools for functional annotation of bacterial genomes.

Secrets

PaperBLAST cannot provide snippets for many of the papers that are published in non-open-access journals. This limitation applies even if the paper is marked as "free" on the publisher's web site and is available in PubmedCentral or EuropePMC. If a journal that you publish in is marked as "secret," please consider publishing elsewhere.

Omissions from the PaperBLAST Database

Many important articles are missing from PaperBLAST, either because the article's full text is not in EuropePMC (as for many older articles), or because the paper does not mention a protein identifier such as a locus tag, or because of PaperBLAST's heuristics. If you notice an article that characterizes a protein's function but is missing from PaperBLAST, please notify the curators at UniProt or add an entry to GeneRIF. Entries in either of these databases will eventually be incorporated into PaperBLAST. Note that to add an entry to UniProt, you will need to find the UniProt identifier for the protein. If the protein is not already in UniProt, you can ask them to create an entry. To add an entry to GeneRIF, you will need an NCBI Gene identifier, but unfortunately many prokaryotic proteins in RefSeq do not have corresponding Gene identifers.

References

PaperBLAST: Text-mining papers for information about homologs.
M. N. Price and A. P. Arkin (2017). mSystems, 10.1128/mSystems.00039-17.

Europe PMC in 2017.
M. Levchenko et al (2017). Nucleic Acids Research, 10.1093/nar/gkx1005.

Gene indexing: characterization and analysis of NLM's GeneRIFs.
J. A. Mitchell et al (2003). AMIA Annu Symp Proc 2003:460-464.

UniProt: the universal protein knowledgebase.
The UniProt Consortium (2016). Nucleic Acids Research, 10.1093/nar/gkw1099.

BRENDA in 2017: new perspectives and new tools in BRENDA.
S. Placzek et al (2017). Nucleic Acids Research, 10.1093/nar/gkw952.

The EcoCyc database: reflecting new knowledge about Escherichia coli K-12.
I. M. Keeseler et al (2016). Nucleic Acids Research, 10.1093/nar/gkw1003.

The MetaCyc database of metabolic pathways and enzymes.
R. Caspi et al (2018). Nucleic Acids Research, 10.1093/nar/gkx935.

CharProtDB: a database of experimentally characterized protein annotations.
R. Madupu et al (2012). Nucleic Acids Research, 10.1093/nar/gkr1133.

The carbohydrate-active enzymes database (CAZy) in 2013.
V. Lombard et al (2014). Nucleic Acids Research, 10.1093/nar/gkt1178.

The Transporter Classification Database (TCDB): recent advances
M. H. Saier, Jr. et al (2016). Nucleic Acids Research, 10.1093/nar/gkv1103.

REBASE - a database for DNA restriction and modification: enzymes, genes and genomes.
R. J. Roberts et al (2015). Nucleic Acids Research, 10.1093/nar/gku1046.

Deep annotation of protein function across diverse bacteria from mutant phenotypes.
M. N. Price et al (2016). bioRxiv, 10.1101/072470.

by Morgan Price, Arkin group
Lawrence Berkeley National Laboratory