ERG1 notes
Workflow
- The falcon/perplexity-lite deep-research recipe was attempted before this manual pass and failed because
this environment has no agentapi command and no provider API key. No
ERG1-deep-research-falcon.md or ERG1-deep-research-perplexity-lite.md file was created; these notes
summarize the cached literature and family rows instead.
- I searched PubMed/Web for newer Candida albicans ERG1 or squalene epoxidase papers. Recent hits were
compound-perturbation, docking, or adjuvant studies that did not change the direct ERG1 functional
model, so no new PMID cache files were needed.
Manual evidence notes
- UniProt Q92206 records Candida ERG1 as the PTHR10835 squalene monooxygenase and gives the curated
Rhea reaction for squalene epoxidation: "Reaction=squalene + reduced [NADPH--hemoprotein reductase]
- O2 = (S)-" [file:genes/CANAL/ERG1/ERG1-uniprot.txt].
- Ryder and Dupont assayed the Candida particulate enzyme before ERG1 was cloned: "A washed
'microsomal' fraction converted radiolabelled squalene to 2,3-oxidosqualene and lanosterol" and its
minimum activity requirements were oxygen, NADH or NADPH, and FAD PMID:6378256.
- Ryder and Dupont then showed that allylamines inhibit the Candida enzyme; naftifine and SF 86-327 were
"potent inhibitors of the Candida epoxidases" PMID:3877503. This supports druggability of the enzyme
but the molecular assignment to ERG1 comes from the later cloning paper.
- Favre and Ryder cloned Candida squalene epoxidase and expressed it in budding yeast; homogenates
"overexpressing the C. albicans protein SE activity was 10-fold higher than the" endogenous activity
PMID:9161422.
- Pasrija et al. conditionally depleted ERG1 and found "a total lack of ergosterol and instead
accumulation of squalene" PMID:15845783. They also reported drug-sensitivity and hyphal defects, but
those are downstream consequences of losing ergosterol-rich membrane structure rather than direct ERG1
processes.
- The later raft-lipid report uses the same logic: ERG1 or IPT1 perturbation "leads to improper surface
localization of" Cdr1p PMID:16246085. This is useful phenotype evidence for sterol/sphingolipid-rich
domains, not a reason to make Cdr1 localization a core ERG1 annotation.
- Roemer et al. placed one ERG1 allele under
MET3p and showed the conditional strain was specifically
hypersensitive to terbinafine: "reduced expression of Ca ERG1 resulted in cells that were hypersensitive
only to the target-specific inhibitor terbinafine" PMID:16607011.
- The CaFT paper reports genome-wide heterozygote responses to many compounds, with "additional inhibitors
of ergosterol biosynthesis, including terbinafine, lovastatin, and dyclonine" in the supplements
PMID:17604452. The xenobiotic-response GO rows inferred from these profiles are target/fitness
perturbations, not evidence that ERG1 executes xenobiotic response.
- The plasma-membrane proteome paper identified 214 proteins by LC-MS/MS PMID:19824013, but the local
cache contains only the abstract and does not expose the ERG1-specific entry. I left the plasma-membrane
row undecided pending the full protein table.
PANTHER rows
PTHR10835 PTN000089417 GO:0004506 F IBD false supports fungal/animal squalene
monooxygenase activity.
PTHR10835 PTN000089417 GO:0005783 C IBD false supports ER localization for the same
broad squalene monooxygenase node.
PTHR10835 PTN000851137 GO:0006696 P IBD false supports the fungal ergosterol biosynthetic
process assertion.