Rv1186c Family assigned · medium auto-curated

H37Rv Rv1186c · MTBC0 mtbc0_001274 · 538 aa · 1336131–1337747 MTBC0 (-) · RefSeq NP_215702.1

Genomic neighbourhood (genome browser)

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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-annotationPucR family transcriptional regulator
Revised (this work)PucR family transcriptional regulator. Pfam: HTH_30 (PF13556.13).
Functional category (TubercuList)conserved hypotheticals

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

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
Interaction analysis of Mycobacterium tuberculosis between the host environment and highly mutated genes from population genetic structure comparison. doi:10.1097/MD.0000000000027125 2021

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.

CRISPRi vulnerability

Vulnerability index 0.76 (95% CI -1.06 to 3.79). 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) ahead of Mycobrowser

Mycobrowser functionFunction unknown

Mycobrowser classes this locus among conserved hypotheticals; the atlas now assigns a functional handle (COG category). Mycobrowser is no longer maintained, so its EC numbers predate recent nomenclature revisions (e.g. the 2018 EC 7 "translocase" class) — most EC differences are re-numberings of the same enzyme, not conflicts.

Orthologues (reciprocal best hits across mycobacteria)

M. bovis Mb1218c · 99.8% identity
M. marinum MMAR_4254 · 80.0% identity
M. smegmatis MSMEG_5120 · 70.4% identity
M. orygis RJtmp_001252 · 99.8% 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 O50442 TrEMBL · unreviewed · Evidence at protein level
UniProt nameConserved protein

UniProt still lists this protein as Conserved protein; the revised annotation above is ahead of the current UniProt record.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category Q Secondary metabolites biosynthesis, transport and catabolism
T Signal transduction mechanisms
eggNOG descriptionPucR C-terminal helix-turn-helix domain
Orthologous groupCOG2508

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 0.386 · purifying
Polymorphic sites (≥ 0.1% of strains) 8 synonymous, 8 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) Actinomycetia

M. canettii dN/dS (deep-divergence selection) 0.967 · 8 consensus substitution(s)
elevated dN/dS vs M. canettii (0.967) — relaxed or positive selection at deep divergence
Genus-wide presence (~53 non-MTBC Mycobacterium) present in 49/53 (92%) · mean identity 77.0% · 4/4 closest MTBAP relatives
conserved across the genus (present in 49/53 non-MTBC Mycobacterium genomes, incl. distant relatives) — an ancient core gene predating the genus radiation
Phylostratum (deepest detected homolog) MTBC-specific Mycobacterium Mycobacteriaceae Corynebacteriales Actinomycetia Bacteria
detected in 3/13 non-Mycobacterium reference genomes (down to Actinomycetia) · mean identity 40.3%
detected across the class Actinomycetia (beyond Corynebacteriales) but not outside the phylum — an Actinobacteria-level ancient gene

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) 19 in the ORF — 0 in the essential state, 0 growth-defect, 19 non-essential, 0 growth-advantage. Saturation 0.895, mean read count 47.1176470588. A region of the protein devoid of TA sites is invisible to this assay: nothing can be inferred about it, in either direction.

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) detected

MS detectiondetected in 7 of 16 independent MS datasets
Integrated abundance2.18 ppm · rank 3153/3519 (10.4th percentile)

Detection by mass spectrometry is direct, experimental evidence that the protein product exists — orthogonal to sequence conservation and to Tn-seq essentiality, and especially decisive for a "hypothetical" locus. Reproducible detection across several independent datasets (PaxDb) makes the existence claim robust; the integrated abundance places the protein in the proteome's dynamic range.

Physico-chemical properties (computed, ProtParam)

Length538 aa
Molecular weight57.5 kDa
Theoretical pI5.65
GRAVY0.093 (hydrophobic)
Aliphatic index110.5
Aromaticity0.039
Instability index30.3 (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
HTH_30PF13556.13 5.2e-21475–533 PucR C-terminal helix-turn-helix domain

Structural search (AlphaFold DB model, Foldseek vs PDB — genome-wide) pLDDT 86.1

PDB hitprobTM-scoreE-valueDescription
9f80-assembly1_A 1.00 0.50 1.3e-08 sig 9f80-assembly1_A Crystal structure of Rv2242 regulator C-terminal fragment (161-414)
3onq-assembly1_B-2 1.00 0.48 7.8e-08 sig 3onq-assembly1_B-2 Crystal Structure of Regulator of Polyketide Synthase Expression BAD_0249 from Bifidobacterium adolescentis
3onq-assembly3_D 1.00 0.47 1.0e-07 sig 3onq-assembly3_D Crystal Structure of Regulator of Polyketide Synthase Expression BAD_0249 from Bifidobacterium adolescentis
2gx5-assembly1_A 1.00 0.66 1.5e-04 sig 2gx5-assembly1_A N-terminal GAF domain of transcriptional pleiotropic repressor CodY
2gx5-assembly1_B 1.00 0.65 3.2e-04 sig 2gx5-assembly1_B N-terminal GAF domain of transcriptional pleiotropic repressor CodY

Foldseek search of the AlphaFold DB model (mean pLDDT 86.1, 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)fadD21 (- strand, 176 bp gap)
Downstream (3' on genome)rocA (+ strand, 84 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).

Transcriptional regulation (signed TRN: ChIP-seq + TFOE) transcription factor

Regulated by (1 TF) Rv1186c (activates)
Regulonthis transcription factor regulates 5 target gene(s)

Regulatory edges from the ISB signed transcriptional regulatory network (TF ChIP-seq binding, Minch 2015 + TF-overexpression response, Rustad 2014). An edge is regulatory evidence (binding and/or expression change), not necessarily direct. For a "hypothetical", membership in a known regulon (e.g. DosR dormancy, PhoP virulence) is a strong physiological-context lead.

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: Rv1188 (proline dehydrogenase), high confidence from genomic context alone (score 840 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv1188 proline dehydrogenase 908 840 ctx neighborhood:783 textmining:451
Rv1187 rocA pyrroline-5-carboxylate dehydrogenase RocA 865 819 ctx neighborhood:783
Rv3124 moaR1 transcriptional regulator MoaR 560 561 ctx cooccurence:550
Rv3055 TetR family transcriptional regulator 498 499 ctx cooccurence:484
Rv2474c hyp hypothetical protein 497 498 ctx cooccurence:495
Rv1185c fadD21 fatty-acid--CoA ligase FadD21 489 489 ctx neighborhood:487
Rv1267c embR transcriptional regulator EmbR 484 484 ctx cooccurence:459
Rv3882c eccE1 ESX-1 secretion system protein EccE1 474 474 ctx cooccurence:474
Rv0513 transmembrane protein 462 462 ctx cooccurence:459
Rv1171 hyp hypothetical protein 459 459 ctx cooccurence:452
Rv1191 hyp hypothetical protein 456 456
Rv1871c hyp hypothetical protein 449 450 ctx cooccurence:431
Rv3071 hyp hypothetical protein 445 446 ctx cooccurence:444
Rv1748 hyp hypothetical protein 443 444 ctx cooccurence:442
Rv3824c papA1 acyltransferase 437 438 ctx cooccurence:437

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

  • Legacy H37Rv annotation: hypothetical protein
  • MTBC0 PGAP product: PucR family transcriptional regulator
  • Pfam (hmmscan --cut_ga): HTH_30 PF13556.13 (E=5e-21)
  • (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 NP_215702.1)
  • Domains: Pfam-A via hmmscan --cut_ga — HTH_30 (PF13556.13)
  • 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 COG2508
  • Curated reference: UniProt O50442 (TrEMBL, unreviewed; Evidence at protein level)
  • 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 86.1)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 24 functional partner(s); context anchor Rv1188
  • Essentiality: genome-wide transposon mutagenesis in H37Rv — DeJesus et al. 2017 (mBio, doi:10.1128/mBio.02133-16, CC BY)
  • Proteomics: integrated mass-spectrometry abundance from PaxDb 5.0 (Huang et al. 2023, doi:10.1016/j.mcpro.2023.100640), taxon 83332 — weighted average of 16 datasets, incl. Schubert et al. 2013 (doi:10.1016/j.chom.2013.04.008) and Albrethsen et al. 2013 (doi:10.1074/mcp.M112.018846)
  • 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)
  • Transcriptional regulation: ISB signed TRN — TF ChIP-seq (Minch et al. 2015, doi:10.1038/ncomms6829) + TF overexpression (Rustad et al. 2014, doi:10.1186/gb-2014-15-11-502)
  • 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

>mtbc0_001274|Rv1186c|
MRIAGVGLGQLLLALDATVVSLVDAPRGLDLPVASTALIDSDDVRLGLAAAAGSADVFFLIGVTDDEAVRWVDDQARQRAPVAIFVKHPSDSVVAGAVRAGSAVVAVEPRARWERLYHLVNHVLEHHGDRADPTDDSGTDLFGLAQSLADRIHGMISIEDAQSHVLAYSASNDEADELRRLSILGRAGPPEHLQWIGQWGIFDALRAGREVVRVAERPELGLRPRLAIGIHQPGVGALRPPVFAGTIWVQQGSQPLADDAEEMLRGAAVLAARIMSRLATQPNTHALRVQQLLGLAELNATTAPVDVSTIARELGVAAEGNATLIGFDTAENRDTAVRHVRLVDVMALSASAFRHDAQVAANGSRIYVLLPQTTTGRAVTSWVRGTISALRAELGVALRAAIAGPVAGLAEVNPARVEVDRVLESAERHPILGQVTSLAEARTTVLLDEIVTLVGTDQRLVDPRIRDLGAQDPVLAQTLRAYLDAFGDIGAAARSLQVHPNTVRYRIRRIEQLLSTSLGDPDVRLLFSLGLRAMERTA