PRR5 (APRR5, At5g24470; UniProt Q6LA42) curation notes

2026-10-06: initial review (module plant_circadian_clock_oscillator)

• Fetched with just fetch-gene ARATH Q6LA42 --alias PRR5. Falcon deep research failed; review based on cached publications.

Key findings

• Represses CCA1/LHY PMID:20233950; binds DNA through the CCT motif PMID:23027938; ChIP-seq direct targets include flowering-time, hypocotyl and cold-stress TFs PMID:23027938.
• Represses PIF4/PIF5 PMID:32165445.
• SCF-ZTL substrate PMID:17693530; with TOC1 the only PRR targeted by ZTL PMID:18562312.
• PRR5-TOC1 heteromer enhances TOC1 nuclear import PMID:20407420.
• O-fucosylation by SPY promotes PRR5 proteolysis PMID:31899321.

Decisions

• TOC1 protein binding: MODIFY to protein heterodimerization activity (GO:0046982), which has a demonstrated functional consequence. SPY binding: REMOVE (PRR5 is the substrate).
• Response to water deprivation IEP (PMID:41566362, a drought GWAS): UNDECIDED, because the abstract does not mention PRR5.
• Import into nucleus (acts upstream, on TOC1): KEEP_AS_NON_CORE.