hsr1 Resolved · high

H37Rv Rv1435c · MTBC0 mtbc0_001535 · 209 aa · 1621686–1622315 (-) · RefSeq NP_215951.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationhypothetical protein
Revised (this work)Hsr1 (host splicing regulator 1), a secreted virulence factor that disrupts host snRNP biogenesis. RefSeq leaves it 'hypothetical'. Secreted Rv1435c/hsr1 targets specific exon-skipping events and facilitates a direct interaction between Mtb phagosomes and U5 snRNA and SNRPF; genetic deletion reverses the splicing changes and attenuates growth ex vivo and in vivo (Chauhan 2025).

Curated reference (UniProt)

UniProt O06823 TrEMBL · unreviewed · Evidence at protein level
UniProt nameProbable conserved proline, glycine, valine-rich secreted protein

Functional vocabulary (eggNOG-mapper, orthology transfer)

Orthologous group29WFS

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 0.623 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 2 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.

Domains (Pfam, hmmscan --cut_ga)

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

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

PartnerProductScoreNo text-miningChannels (≥400)
Rv1005c pabB para-aminobenzoate synthase component I 820 809 coexpression:648 experimental:461
Rv1609 trpE anthranilate synthase component I 819 808 coexpression:647 experimental:461
Rv2386c mbtI salicylate synthase 819 807 coexpression:646 experimental:461
Rv1006 hyp hypothetical protein 775 775 ctx cooccurence:774
Rv1868 hyp hypothetical protein 773 773 ctx cooccurence:773
Rv2894c xerC tyrosine recombinase XerC 780 770 coexpression:770
Rv2047c hyp hypothetical protein 784 761 ctx cooccurence:756
Rv2192c trpD anthranilate phosphoribosyltransferase 781 751 coexpression:737
Rv1612 trpB tryptophan synthase subunit beta 776 746 coexpression:731
Rv3899c hyp hypothetical protein 745 746 ctx cooccurence:744
Rv1613 trpA tryptophan synthase subunit alpha 775 745 coexpression:730
Rv3033 hyp hypothetical protein 745 745 ctx cooccurence:745
Rv0013 trpG anthranilate synthase component II 774 744 coexpression:729
Rv0063 oxidoreductase 740 740 coexpression:740
Rv2082 hyp hypothetical protein 738 739 ctx cooccurence:738

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

  • Secreted protein interacting with host splicing factors; targets exon-skipping (Chauhan 2025, PMID 40601628)
  • Links Mtb phagosomes to U5 snRNA / SNRPF; Δhsr1 attenuated in macrophages and mice
  • Named hsr1
  • 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_215951.1)
  • 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 29WFS
  • Curated reference: UniProt O06823 (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)
  • Model confidence: ESMFold per-residue pLDDT (mean 69.7, low)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 119 functional partner(s)
  • Primary literature: Chauhan K, Datta D, Kapoor Y, Passricha N, Dutt R, Arora N, Das M, Rao K, Singh L, Gautam A, et al. (2025). A Mycobacterium tuberculosis secreted virulence factor Rv1435c/hsr1 disrupts host snRNP biogenesis Proc Natl Acad Sci USA 122(27):e2423349122. doi:10.1073/pnas.2423349122 PMID:40601628

Ancestral MTBC0 protein sequence

>mtbc0_001535|Rv1435c|hsr1
MTLMAIVNRFNIKVIAGAGLFAAAIALSPDAAADPLMTGGYACIQGMAGDAPVAAGDPVAAGGPAAAGACSAALTDMAGVPFVAPGPVPAAAPVPIGAPVPIPGAPVPIPGAPVPIPGAPVPIPGGPVPIPGAPVPVPAVPAPVIPVGTPLIALGPVLAGAPGDGVVSAPIIGMSGVKDALTDPAPAGGPVPGQPVLPGPSASAPAGAR