sigD Resolved · high auto-curated

H37Rv Rv3414c · MTBC0 - · 212 aa · 3833038–3833676 (-) · RefSeq NP_217931.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)ECF RNA polymerase sigma factor SigD
MTBC0 PGAP re-annotation
Revised (this work)ECF RNA polymerase sigma factor SigD. Pfam: Sigma70_r2 (PF04542.21), Sigma70_r4_2 (PF08281.19), Sigma70_r4 (PF04545.23).

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).

Curated reference (UniProt)

UniProt P9WGG9 SwissProt · reviewed · Evidence at protein level
UniProt nameECF RNA polymerase sigma factor SigD
Curated functionSigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released. Extracytoplasmic function (ECF) sigma factors are held in an inactive form by an anti-sigma factor until released by regulated intramembrane proteolysis.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category K Transcription
Preferred namesigD
eggNOG descriptionBelongs to the sigma-70 factor family. ECF subfamily
Orthologous groupCOG1595
KEGG orthology K03088
Gene Ontology (50) GO:0000988, GO:0000990, GO:0002791, GO:0003674, GO:0006355, GO:0006950, GO:0008150, GO:0009266, GO:0009405, GO:0009408, GO:0009628, GO:0009889 +38 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 0.364 · purifying
Polymorphic sites (≥ 0.1% of strains) 2 synonymous, 2 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.

Domains (Pfam, hmmscan --cut_ga)

PfamAccessioni-EvalueResiduesDescription
Sigma70_r2PF04542.21 1.2e-1250–119 Sigma-70 region 2
Sigma70_r4_2PF08281.19 2.5e-10152–201 Sigma-70, region 4
Sigma70_r4PF04545.23 2.5e-09154–202 Sigma-70, region 4

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

Closest characterised functional partner: rsdA (anti-sigma-D factor RsdA), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3413c rsdA anti-sigma-D factor RsdA 999 1000 ctx neighborhood:882 cooccurence:488 experimental:999
Rv2721c hyp hypothetical protein 785 785 coexpression:785
Rv3415c hyp hypothetical protein 783 784 ctx neighborhood:783
Rv1477 ripA peptidoglycan endopeptidase RipA 774 774 coexpression:770
Rv3810 pirG cell surface protein 778 747 coexpression:746
Rv3717 hyp hypothetical protein 742 742 coexpression:734
Rv0063 oxidoreductase 734 734 coexpression:734
Rv0179c lprO lipoprotein LprO 730 730 coexpression:730
Rv0312 hyp hypothetical protein 714 703 coexpression:703
Rv1987 chitinase 651 652 coexpression:651
Rv2145c wag31 cell wall synthesis protein Wag31 642 643 coexpression:586
Rv3221A rshA anti-sigma factor RshA 686 557
Rv1221 sigE ECF RNA polymerase sigma factor SigE 551 552 ctx cooccurence:549
Rv3911 sigM ECF RNA polymerase sigma factor SigM 894 513 ctx cooccurence:510 textmining:792
Rv0736 rslA anti-sigma-L factor RslA 539 486

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 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): ECF RNA polymerase sigma factor SigD
  • Pfam (hmmscan --cut_ga): Sigma70_r2 PF04542.21 (E=1e-12), Sigma70_r4_2 PF08281.19 (E=3e-10), Sigma70_r4 PF04545.23 (E=3e-09)
  • (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_217931.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Sigma70_r2 (PF04542.21), Sigma70_r4_2 (PF08281.19), Sigma70_r4 (PF04545.23)
  • 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 COG1595
  • Curated reference: UniProt P9WGG9 (SwissProt, reviewed; 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)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 42 functional partner(s); context anchor rsdA
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>H37Rv|Rv3414c|sigD
MVDPGVSPGCVRFVTLEISPSMTMQGERLDAVVAEAVAGDRNALREVLETIRPIVVRYCRARVGTVERSGLSADDVAQEVCLATITALPRYRDRGRPFLAFLYGIAAHKVADAHRAAGRDRAYPAETLPERWSADAGPEQMAIEADSVTRMNELLEILPAKQREILILRVVVGLSAEETAAAVGSTTGAVRVAQHRALQRLKDEIVAAGDYA