Rv1584c Family assigned · medium

H37Rv Rv1584c · MTBC0 mtbc0_001691 · 73 aa · 1798267–1798488 MTBC0 (-) · RefSeq NP_216100.1

Genomic neighbourhood (genome browser)

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+ strand − strand ripD (Rv1566c) — family_assigned: NlpC/P60 family peptidoglycan-binding protein RipD bioA (Rv1568) — requalified: adenosylmethionine--8-amino-7-oxononanoate transaminase bioA bioD (Rv1570) — requalified: dethiobiotin synthase Rv1571 (Rv1571) — family_assigned: 2'-5' RNA ligase family protein Rv1573 (Rv1573) — dark: hypothetical protein Rv1576c (Rv1576c) — requalified: phage major capsid protein Rv1576c Rv1578c (Rv1578c) — family_assigned: phage terminase small subunit P27 family est12 (Rv1579c) — requalified: hypothetical protein Rv1580c (Rv1580c) — family_assigned: hypothetical protein Rv1581c (Rv1581c) — dark: hypothetical protein Rv1582c (Rv1582c) — family_assigned: phage/plasmid primase%2C P4 family Rv1582c Rv1583c (Rv1583c) — dark: DUF2742 domain-containing protein Rv1584c (Rv1584c) — family_assigned: hypothetical protein Rv1585c (Rv1585c) — family_assigned: hypothetical protein Rv1586c (Rv1586c) — family_assigned: recombinase family protein Rv1586c bioB (Rv1589) — requalified: biotin synthase BioB bioB Rv1590 (Rv1590) — family_assigned: hypothetical protein Rv1591 (Rv1591) — dark: DUF2567 domain-containing protein Rv1592c (Rv1592c) — family_assigned: lipase family protein Rv1592c Rv1593c (Rv1593c) — family_assigned: NUDIX domain-containing protein nadB (Rv1595) — requalified: L-aspartate oxidase nadB nadC (Rv1596) — requalified: carboxylating nicotinate-nucleotide diphosphorylase nadC Rv1597 (Rv1597) — family_assigned: methyltransferase domain-containing protein 1 788 kb 1 792 kb 1 796 kb 1 800 kb 1 804 kb 1 808 kb

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)phage protein
MTBC0 PGAP re-annotationhypothetical protein
Revised (this work)Prophage phiRv1 recombination-directionality factor (RDF/excisionase). RefSeq leaves it of unknown function. In the phiRv1 prophage-like element, the serine integrase Rv1586c catalyses integration/excision and the small basic Rv1584c protein controls the directionality of recombination (Bibb 2002).
Functional category (TubercuList)insertion seqs and phages

In the literature (TB corpus sweep) 1 publication

1 TB publication mentions this gene. 1 publication(s) discuss this gene (1 in a M. tuberculosis context).

PublicationDate
Integration and excision of the Mycobacterium tuberculosis prophage-like element, phiRv1. doi:10.1046/j.1365-2958.2002.03130.x 2002

This layer CITES the literature and adds context; it does not change the verdict or the function stated elsewhere in this fiche. This distinguishes a gene that is dark because nobody has looked from one that is dark despite having been studied. Source: PubMed (whole): H37Rv locus tag + GENE NAME + ortholog identifiers (Mb…, MMAR_…, MSMEG_…, ML…, MAB_…), under a mycobacterial context filter; hits verified against the abstract text. Species-context counts distinguish M. tuberculosis literature from literature on other mycobacteria. phase76/phase77, 2026-07-13.

Genomic-neighbour overlap (structural caveat) co-directional · 2 % of gene

NeighbourRv1583c (Rv1583c, - strand)
Overlap4 bp, 2 % of this gene's length

co-directional overlap: ordinary (e.g. shared stop/start codons in an operon), not the Rv2438A-type artefact P20.1, derived from GFF3 gene coordinates, 2026-08-03.

Conditional expression context (iModulons)

Member of 1 independently-modulated gene set(s): PyrR (pyrR).

iModulon membership (independently-modulated gene sets from a 647-sample RNA-seq compendium): the conditional co-expression context. Co-expression is a regulatory context, NOT a molecular function. Source: iModulonDB / modulome_mtb (Yoo 2022).

CRISPRi vulnerability

Vulnerability index 0.73 (95% CI -0.34 to 2.35). 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).

Orthologues (reciprocal best hits across mycobacteria)

M. bovis Mb1610c · 98.6% 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 O06606 TrEMBL · unreviewed · Predicted
UniProt namePossible PhiRv1 phage protein

Functional vocabulary (eggNOG-mapper, orthology transfer)

Orthologous group28RTI

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.

Outgroup conservation (beyond the MTBC) Mycobacterium

Genus-wide presence (~53 non-MTBC Mycobacterium) present in 4/53 (8%) · mean identity 58.1% · 1/4 closest MTBAP relatives
present in a subset of the genus (4/53 NTM; in 1 of the 4 closest MTBAP relatives) — partial/intermediate conservation
Phylostratum (deepest detected homolog) MTBC-specific Mycobacterium Mycobacteriaceae Corynebacteriales Actinomycetia Bacteria

short ORF (73 aa) a shallow stratum may reflect homology-detection failure, not true youth
present across the genus Mycobacterium (NTM) but not detected in any non-Mycobacterium genome — a Mycobacterium-genus 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.

Regions of Difference (lineage deletions)

RDGene overlapDeleted in lineages
RD3 100% L2, L7, L4.12, L4.14, L6, L9, Microti, Orygis, Canettii (98%), L4.3 (92%), L4.7 (83%), L4.2 (62%)
149 100% L2, L7, L4.12, L4.14, L6, L9, Microti, Orygis, Canettii (98%), L4.3 (92%), L4.7 (83%), L4.2 (62%)
DS5 100% L2, L7, L4.12, L4.14, L6, L9, Microti, Orygis, Canettii (98%), L4.3 (92%), L4.7 (83%), L4.2 (62%)

This locus overlaps a Region of Difference — a large deletion that is absent in the listed lineages (from the consolidated MTBC RD analysis over ~145 000 strains; H37Rv coordinates). The gene-overlap column is the fraction of the gene inside the RD. RD deletions are classic lineage markers (e.g. RD9 absent in the animal / M. africanum lineages); a gene deleted in a whole lineage is dispensable there.

Essentiality (transposon mutagenesis)

DeJesus 2017 callNE · non-essential
What the call meansnon-essential
TA sites (Himar1) 3 in the ORF — 0 in the essential state, 0 growth-defect, 3 non-essential, 0 growth-advantage. Saturation 1.000, mean read count 134.333333333. A region of the protein devoid of TA sites is invisible to this assay: nothing can be inferred about it, in either direction.
CaveatStatistically thin call: only 3 TA (Himar1) sites in the whole ORF (atlas median 13; genes under 300 nt typically have very few). A DeJesus 2017 call built on so few independent observations is less robust than the same call on a longer gene, in either direction. Cross-check against the CRISPRi vulnerability index (independent of TA-site density) and, if this gene overlaps a neighbour (see Genomic-neighbour overlap section below), verify how many of its TA sites actually fall inside its own ORF. (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)

Length73 aa
Molecular weight8.0 kDa
Theoretical pI10.69
GRAVY-0.321 (hydrophilic)
Aliphatic index93.8
Aromaticity0.041
Instability index65.2 (unstable)

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)

No Pfam-A domain above the gathering threshold (or not yet scanned).

Genomic context (neighbours & predicted operon) operon of 3

Upstream (5' on genome)Rv1583c (- strand, -4 bp gap)
Downstream (3' on genome)Rv1585c (- strand, 55 bp gap)
Predicted operon Rv1582c · Rv1583c · Rv1584c

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)

Regulated by (2 TF) whiA (activates) · whiB2 (activates)

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: Rv1583c (phage protein), high confidence from genomic context alone (score 779 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1583c phage protein 780 779 ctx neighborhood:778
Rv1582c phage protein 777 777 ctx neighborhood:773
Rv1586c phage integrase 857 630 ctx neighborhood:618 textmining:630
Rv1587c hyp hypothetical protein 616 616 ctx neighborhood:605
Rv1585c phage protein 931 612 ctx neighborhood:605 textmining:830
Rv1588c hyp hypothetical protein 608 607 ctx neighborhood:605
Rv1581c phage protein 452 452 ctx neighborhood:447
Rv1579c phage protein 439 439 ctx neighborhood:436
Rv1580c phage protein 439 438 ctx neighborhood:436
Rv2657c prophage protein 464 96 textmining:432
Rv0595c vapC4 ribonuclease VapC4 437 50 textmining:432
Rv2310 excisionase 870 47 textmining:870
Rv1573 phage protein 517 47 textmining:514
Rv3750c vapB50 excisionase 698 46 textmining:697
Rv1802 PPE30 PPE family protein PPE30 442 46 textmining:440

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

  • phiRv1 prophage; small basic protein controlling recombination directionality (Bibb 2002, PMID 12354222)
  • Curated from the literature crible (project 'Still unknown gene function', 2026-06-09)

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_216100.1)
  • Domains: Pfam-A via hmmscan --cut_ga — none above threshold
  • 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 28RTI
  • Curated reference: UniProt O06606 (TrEMBL, unreviewed; Predicted)
  • 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 89.5)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 21 functional partner(s); context anchor Rv1583c
  • 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
  • Regions of Difference: consolidated MTBC RD analysis (H37Rv coordinates); RD framework from Brosch et al. 2002 (doi:10.1073/pnas.052548299) and Gagneux & Small 2007 (doi:10.1016/S1473-3099(07)70108-1)
  • 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: Bibb LA, Hatfull GF (2002). Integration and excision of the Mycobacterium tuberculosis prophage-like element, phiRv1 Mol Microbiol 45(6):1515-26. doi:10.1046/j.1365-2958.2002.03130.x PMID:12354222

Ancestral MTBC0 protein sequence

>mtbc0_001691|Rv1584c|
MSTIYHHRGRVAALSRSRASDDPEFIAAKTDLVAANIADYLIRTLAAAPPLTDEQRTRLAELLRPVRRSGGAR