PIF1 / PIL5 (Q8GZM7; At2g20180) curation notes

Session 2026-10-05/06 (phytochrome_photomorphogenesis module curation).

• Falcon deep research: the first attempt timed out, but a retry produced PIF1-deep-research-falcon.md, which was used as retrieval support. Claims used in the review were traced to primary literature.
• Identity check: PIF1_ARATH, Q8GZM7, 478 aa.

Key evidence

• Pfr phytochrome binding PMID:15448264; PMID:15486102.
• Rapid light-induced phosphorylation/degradation PMID:18539749; CK2 contributes PMID:21330376; SPA1 kinase PMID:31527679; CUL4-COP1-SPA E3 PMID:26037329.
• Cofactor of COP1 in darkness PMID:24858936.
• Direct targets: GAI/RGA PMID:17449805, SOM PMID:21467583, PORC PMID:18591656, 166 direct targets in seeds PMID:19244139.
• Germination repression PMID:16303558.

Decisions

• protein binding: phyB rows -> MODIFY to phytochrome binding; PIF3/HFR1 -> heterodimerization; others REMOVE per policy.
• Four IEP rows from PMID:23708772 (review/meta-analysis of expression) -> MARK_AS_OVER_ANNOTATED.
• Chlorophyll / heme / GA biosynthesis rows kept as non-core (transcriptional, indirect).