SMXL6 (At1g07200, UniProt Q9LML2) curation notes

Context: strigolactone_signaling_shoot_branching module. Falcon deep research failed (all
providers); notes from cached publications.

Function

• SMXL6/7/8 are co-orthologs of rice D53 and promote shoot branching PMID:26546447.
• SL induces D14/MAX2-dependent ubiquitination and degradation PMID:26546446.
• EAR-motif/TPR2-dependent transcriptional repression; BRC1 repressed PMID:26546446.
• Nuclear PMID:26546446.
• SMXL6 binds DNA directly at SMXL6/7/8 promoters [PMID:32528176, abstract only].
• SMXL7 functions in the nucleus; EAR partly dispensable PMID:27317673.
• Drought: smxl6,7,8 triple more drought resistant PMID:32295207; DWA1 interaction and SnRK2.3 promoter binding PMID:37759806.

Curation decisions

• protein folding chaperone (IBA from deep Clp node, P9WPC9) and derived protein folding (IEA): REMOVE (functional divergence of SMXL clade).
• ATP binding / ATP hydrolysis (InterPro): MARK_AS_OVER_ANNOTATED (not demonstrated).
• protein binding (D14, DWA1): REMOVE as uninformative (interactions themselves real).
• Cytoplasm (AtSubP): over-annotated; chloroplast (SMXL6 AtSubP): REMOVE.
• NEW: GO:0003714 transcription corepressor activity (IDA), GO:2000032 regulation of secondary shoot formation (IMP), GO:1902348 cellular response to strigolactone (IDA); GO:0000976 transcription cis-regulatory region binding (IDA, PMID:32528176).