Rv0742 Family assigned · medium auto-curated

H37Rv Rv0742 · MTBC0 - · 175 aa · 832981–833508 H37Rv (+) · RefSeq YP_177749.1

Genomic neighbourhood (genome browser)

Open in full genome browser →

This gene (outlined) in its genomic context; arrows are neighbouring genes coloured by verdict. Click any gene to navigate. Pan and zoom in the full browser.

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotation
Revised (this work)Contains PE (PF00934.26) domain(s); putative function inferred from the domain architecture.
Functional category (TubercuList)PE/PPE

Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.

Annotated on the H37Rv protein: this gene has no 1:1 ancestral MTBC0 anchor (PE/PPE, paralogue, IS element, or otherwise unanchored CDS).

In the literature (TB corpus sweep) 1 publication

Found under: H37Rv (1).

1 TB publication mentions this gene. 1 publication(s) mention this gene (title/abstract), verified against the text. The atlas states the function; these are the primary sources that discuss it.

PublicationDate
The PE_PGRS Proteins of Mycobacterium tuberculosis Are Ca(2+) Binding Mediators of Host-Pathogen Interaction. doi:10.1021/acs.biochem.6b00289 2016

This layer CITES the literature, it does not change the verdict or the function. A gene may be heavily studied (as an antigen, a resistance determinant, a drug target) while its molecular function is settled elsewhere in the fiche. This distinguishes a gene that is dark because nobody has looked from one that is dark despite having been studied. Source: PubMed (whole), MULTI-ALIAS sweep: H37Rv locus tag AND every ortholog identifier (M. bovis Mb…, M. marinum MMAR_…, M. smegmatis MSMEG_…, M. leprae ML…, M. abscessus MAB_…), each hit VERIFIED against the abstract text (word-boundary regex). phase73/phase75, 2026-07-13.

Intrinsic disorder (sequence + structure) highly disordered

Predicted disorder100% of residues (metapredict) · mean AlphaFold pLDDT 92.4
Disordered regions1 IDR(s), longest 175 aa [0-175]

sequence-based disorder is high but AlphaFold folds it confidently (pLDDT>=70): treat the disorder call with caution (possible metapredict over-call)

A property (biophysics), not a function. No LLPS/condensate claim is made from disorder alone. Verdict unchanged. Source: metapredict v3 (Emenecker/Holehouse) per-residue disorder + AlphaFold mean pLDDT (annotation_mtbc P16.13).

CRISPRi vulnerability

Vulnerability index -0.01 (95% CI -1.74 to 1.91). A more negative index = more vulnerable to knockdown (better drug-target quality); indicative threshold VI ≤ -6 = highly vulnerable.

Quantitative CRISPRi knockdown, graded (finer than binary Tn-seq essentiality). Source: CRISPRi vulnerability index (Bosch 2021, pebble.rockefeller.edu).

Legacy record & comparison (Mycobrowser)

Mycobrowser functionFunction unknown

The legacy Mycobrowser record is shown for verification. Mycobrowser is no longer maintained; its EC numbers predate recent nomenclature revisions, so a class change usually reflects re-numbering, not a conflict.

Orthologues (reciprocal best hits across mycobacteria)

M. bovis Mb0763 · 100.0% identity
M. marinum MMAR_0608 · 75.4% identity
M. orygis RJtmp_000784 · 100.0% identity

Reciprocal-best-hit orthologues (DIAMOND) against the Mycobrowser reference proteomes. A missing species is informative: e.g. a gene absent from M. leprae was likely lost in its reductive genome evolution. Locus tags link to Mycobrowser.

Curated reference (UniProt)

UniProt I6Y8K5 SwissProt · reviewed · Inferred from homology
UniProt namePE-PGRS family protein PE_PGRS8

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category I Lipid transport and metabolism
eggNOG descriptionacetylesterase activity
Orthologous groupCOG0657
EC number EC 3.1.1.3
KEGG orthology K01046
KEGG pathways map00561, map01100
KEGG modules M00098
Gene Ontology (54) GO:0003674, GO:0003824, GO:0004806, GO:0005488, GO:0005575, GO:0005618, GO:0005623, GO:0005886, GO:0006950, GO:0008150, GO:0009405, GO:0009605 +42 more

Orthology-based transfer (eggNOG 5.0.2, diamond). EC/KO/GO/CAZy are computed annotations, not manual curation; cross-check against the primary literature before treating a specific reaction as established.

Conservation & selection (intra-MTBC, 145 209 strains)

pN/pS 1.183 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 3 missense, 0 nonsense, 0 frameshift

pN/pS from segregating SNPs (singletons removed) normalised by possible sites. Low pN/pS = purifying selection (a strong signal that a "hypothetical" is a real, constrained gene). A high pN/pS is ambiguous: relaxed constraint or positive selection (drug resistance, antigenic variation) inflate it; e.g. rpoB/katG/pncA score high here for resistance, not loss of function. A clonal disruption (one allele over a clade) suggests lineage pseudogenisation; a convergent one (many independent alleles) is typical of resistance loss-of-function.

Outgroup conservation (beyond the MTBC) MTBC-specific

Genus-wide presence (~53 non-MTBC Mycobacterium) present in 0/53 (0%) · 0/4 closest MTBAP relatives
NOT MTBC-specific despite passing the strict presence filter: no hit at pident>=30 & qcov>=50 across the 53 non-MTBC genomes, BUT sub-threshold tblastn hit(s) exist (M_persicum:84.0id/43cov;n=19;mtbap=4) — the gene is PRESENT BUT DIVERGENT in at least one non-MTBC Mycobacterium, not a genus-level innovation. Do not frame as MTBC-specific nor as a host-adaptation factor. Human non-homology, if needed, must be established directly (BLASTp vs human proteome), never inferred from this field.
Phylostratum (deepest detected homolog) MTBC-specific Mycobacterium Mycobacteriaceae Corynebacteriales Actinomycetia Bacteria

absent from the whole genus and from all outgroups tested — a candidate MTBC-specific innovation (confirm by synteny; rule out detection failure for short/divergent ORFs)

Two orthogonal outgroup signals. M. canettii (the immediate outgroup) gives a deep-divergence dN/dS (a low value confirms a constrained, real gene; shown as confident only at ≥8 substitutions, else flagged low-power). Genus-wide presence/absence (tblastn vs assembled non-MTBC genomes) places the gene on the ancient-core ↔ MTBC-specific axis: a gene absent even from the closest MTBAP relatives is a candidate MTBC-specific innovation (possible host-adaptation factor, to confirm by synteny). The phylostratum extends that axis outside the genus (tblastn vs 13 reference genomes spanning Mycobacteriaceae → Corynebacteriales → Actinomycetia → outside the phylum): it is the deepest clade in which a homolog is still detected, i.e. a proxy for gene age. Read it with the null model in mind: a shallow (young) stratum can also reflect homology-detection failure for short or fast-evolving ORFs, so it is a descriptive axis, not a proof of novelty.

Essentiality (transposon mutagenesis)

DeJesus 2017 callNE · non-essential
What the call meansnon-essential
TA sites (Himar1) 6 in the ORF — 0 in the essential state, 0 growth-defect, 6 non-essential, 0 growth-advantage. Saturation 1.000, mean read count 164.666666667. A region of the protein devoid of TA sites is invisible to this assay: nothing can be inferred about it, in either direction.
CaveatRead with some caution: only 6 TA (Himar1) sites in the whole ORF (atlas median 13). The DeJesus 2017 call rests on fewer independent observations than for a longer gene. If this gene overlaps a neighbour (see Genomic-neighbour overlap section below), some of these 6 sites may fall inside the neighbour's ORF rather than its own, leaving even fewer truly informative sites than the raw count suggests. (P20.3)

Genome-wide Himar1 transposon essentiality in H37Rv (DeJesus 2017). An essential call (ES/ESD/GD) is strong, independent evidence that a "hypothetical" locus encodes a functional, selectively required gene — orthogonal to intra-species conservation.

Proteomics (mass spectrometry) not detected

Not detected in the mass-spectrometry datasets integrated by PaxDb. This is not evidence of absence: low-abundance, condition-specific, or MS-refractory proteins (e.g. small, highly hydrophobic, or repetitive PE/PPE families with few tryptic peptides) are systematically under-sampled.

Physico-chemical properties (computed, ProtParam)

Length175 aa
Molecular weight15.5 kDa
Theoretical pI4.22
GRAVY0.668 (hydrophobic)
Aliphatic index90.4
Aromaticity0.051
Instability index18.3 (stable)

Computed from the ancestral MTBC0 sequence with the ExPASy ProtParam method (Biopython). Descriptive biophysical context: a positive GRAVY flags a hydrophobic (often membrane) protein, a high instability index (>40) predicts a short in-vitro half-life, an extreme pI hints at compartment or binding partner.

Domains (Pfam, hmmscan --cut_ga)

PfamAccessioni-EvalueResiduesDescription
PEPF00934.26 2.4e-344–93 PE family

Structural search (AlphaFold DB model, Foldseek vs PDB — genome-wide) pLDDT 92.4

PDB hitprobTM-scoreE-valueDescription
5xfs-assembly1_A 1.00 0.98 6.8e-05 sig 5xfs-assembly1_A Crystal structure of PE8-PPE15 in complex with EspG5 from M. tuberculosis

Foldseek search of the AlphaFold DB model (mean pLDDT 92.4, gated at 70) against the PDB — a genome-wide extension of the ESMFold dark-gene search that also covers proteins beyond the single-sequence length limit. Confident structural neighbours (E < 0.01) shown.

Genomic context (neighbours & predicted operon)

Upstream (5' on genome)Rv0740 (+ strand, 677 bp gap)
Downstream (3' on genome)Rv0743c (- strand, 377 bp gap)

Neighbours from the H37Rv annotation (+ strand). The operon is predicted by co-directional intergenic distance (same strand, gaps ≤50 bp) — a transcription-unit hypothesis, not a mapped TSS. For a "hypothetical", co-transcription with a characterised operon is a concrete functional lead (complements the STRING neighborhood channel below).

Functional interaction network (STRING v12, guilt-by-association)

Explore full network →

Node colour = verdict, dashed = hypothetical; edge colour = evidence (green experimental, orange genomic-context, grey co-expression), width ∝ score. Click a partner to open its page; "Explore full network" to walk the graph.

Closest characterised functional partner: Rv0741 (Probable transposase (fragment); Rv0741, (MTV041.15), len: 104 aa. Probable truncated transposase for IS1557, showing similarity to transpos), medium confidence from genomic context alone (score 506 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv1364c sigma factor regulatory protein 520 515 coexpression:500
Rv0741 Probable transposase (fragment); Rv0741, (MTV041.15), len: 104 aa. Probable truncated transposase for IS1557, showing similarity to transpos 506 506 ctx neighborhood:506

STRING combines evidence channels (neighborhood, fusion, cooccurrence, coexpression, experimental, database, text-mining) into a 0–1000 score. The ctx badge marks edges carried by the genomic-context channels (conserved neighborhood, fusion, phylogenetic co-occurrence), which are independent of orthology and structure and the strongest signal for an unknown gene. The exp badge marks an experimentally-supported partner (measured interaction, experimental/database channel ≥400) as opposed to a purely predicted one — but note that the M. tuberculosis experimental interactome is dominated by a noisy bacterial-two-hybrid screen, so a strong measured link that contradicts the operon/localisation context is likely a false positive. The no text-mining column recomputes the score from data alone, so a link that does not depend on the literature is visible. Association is a function hypothesis, not proof: corroborate with the operon context and the primary literature before assigning a function.

Evidence

  • Annotation from H37Rv (no MTBC0 1:1 anchor; H37Rv protein used): hypothetical protein
  • Pfam (hmmscan --cut_ga): PE PF00934.26 (E=2e-34)
  • (auto-curated by rules from PGAP + Pfam + Foldseek; not hand-reviewed)

Sources

  • Ancestral sequence & coordinates: Harrison LB et al. (2024), An imputed ancestral reference genome for the MTBC, doi:10.1101/2023.09.07.556366
  • Product annotation: NCBI PGAP on MTBC0; legacy from H37Rv NC_000962.3 (RefSeq YP_177749.1)
  • Domains: Pfam-A via hmmscan --cut_ga — PE (PF00934.26)
  • Sequence-level signal: ESM Atlas (EvolutionaryScale × BioHub) — exploratory
  • Controlled vocabulary: eggNOG-mapper 2.1.12 (Cantalapiedra et al. 2021, doi:10.1093/molbev/msab293), eggNOG 5.0 DB (Huerta-Cepas et al. 2019) — OG COG0657
  • Curated reference: UniProt I6Y8K5 (SwissProt, reviewed; Inferred from homology)
  • Intra-MTBC selection: pN/pS and disruption from SPDI variants of 145 209 MTBC strains (this work, local collection vs H37Rv NC_000962.3)
  • Genome-wide structure: AlphaFold DB model (Jumper et al. 2021, doi:10.1038/s41586-021-03819-2; Varadi et al. 2024, doi:10.1093/nar/gkad1011) searched vs PDB with Foldseek (mean pLDDT 92.4)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 2 functional partner(s); context anchor Rv0741
  • Essentiality: genome-wide transposon mutagenesis in H37Rv — DeJesus et al. 2017 (mBio, doi:10.1128/mBio.02133-16, CC BY)
  • Functional category: TubercuList scheme (Cole et al. 1998, doi:10.1038/31159), via Mycobrowser (Kapopoulou et al. 2011, doi:10.1016/j.tube.2010.09.006)
  • Orthologues: reciprocal best hits (DIAMOND, Buchfink et al. 2021, doi:10.1038/s41592-021-01101-x) against Mycobrowser release 5 reference proteomes
  • Genomic context / operon: H37Rv annotation; operon predicted by co-directional intergenic distance (Salgado et al. 2000, doi:10.1073/pnas.030539397)
  • Physico-chemical properties: ExPASy ProtParam method via Biopython (Gasteiger et al. 2005), computed from the MTBC0 sequence
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>H37Rv|Rv0742|
MSFVIAAPEAIAAAATDLASIGSTIGAANAAAAANTTAVLAAGADQVSVAIAAAFGAHGQAYQALSAQAATFHIQFVQALTAGAGSYAAAEAASAASITSPLLDAINAPFLAALGRPLIGNGADGAPGTGAAGGAGGLLFGNGGAGGSGAPGGAGGLLFGNGGAGGPGASGGALG