BEH2 (At4g36780; UniProt Q94A43) - manual literature synthesis

No deep-research API was available; this summary was compiled manually from cached
publications (publications/PMID_*.md) and PubMed searches ("BEH2 AND Arabidopsis"
returned 5 records, all reviewed here).

Identity and family

• BEH2 = BES1/BZR1 homolog protein 2, 318 aa, one of six BZR1/BES1 family members
  (BZR1, BES1, BEH1-BEH4). UniProt: "Belongs to the BZR/LAT61 family." Pfam PF05687
  (BES1_N), InterPro IPR008540 (BES1_N) and IPR033264 (BZR); region 16..97 "Required for
  DNA-binding" is assigned by similarity (ECO:0000250) to BES1/BZR1.
• PMID:37926922

Regulation by GSK3-like kinases (phosphorylation)

• Rozhon et al. 2010 (full text): ASKtheta (group III GSK3) was used as yeast two-hybrid
  bait and BEH2 was recovered PMID:20128883
• BIN2 also interacts in Y2H PMID:20128883
• Direct phosphorylation in vitro PMID:20128883
  and in protoplasts PMID:20128883,
  blocked by the GSK3 inhibitor bikinin.
• UniProt PTM: "Phosphorylated. Phosphorylation increases protein degradation." (ECO:0000269, PubMed:15680330, Yin et al. 2005; abstract-only in cache).
• UniProt MUTAGEN P222L (BEH2m, the bzr1-1D/bes1-D-equivalent proline): "increased stability of the protein and constitutive brassinosteroids response" (no evidence tag on the line; record cites PMID:15680330).
• Otani et al. 2022 (full text): BL shifts BEH2-GFP to the dephosphorylated form and brassinazole to the phosphorylated form (Supplementary Fig. 5).

Subcellular localization

• CFP-BEH2 in tobacco leaves PMID:20128883
• BEH2-GFP in onion cells and Arabidopsis roots, independent of BR status PMID:35695417
• Kim et al. 2024 (abstract only) PMID:37926922

Transcriptional function and BR signalling

• Overexpression rescues bri1-5 and produces enhanced BR responses PMID:37926922
• RNA-seq: PMID:37926922
• Otani 2022: BEH2 overexpression (6x) altered >=1131 genes; ~20-35% BR-regulated; GO enrichment of DEGs pointed to stress response and photosynthesis (overexpression-derived, indirect; not a basis for BP annotation).
• No direct DNA-binding assay (EMSA/ChIP) for BEH2 itself was found in the cached
  literature; DNA binding (BRRE/E-box) is inferred from the conserved BES1_N domain
  and family members BZR1/BES1 (e.g. PMID:15680330 shows BES1 binds E-boxes).

BEH2 transcription is itself BR-repressed

• PMID:35695417; BES1 more than BZR1 mediates this.
• Expression: preferentially roots and leaf margins (PMID:35695417); family expression profiles in PMID:32508516.

Genetics

• The bes1 bzr1 beh1 beh3 beh4 quintuple mutant (qui-1) is male sterile; BEH2 was not
  included because no valid T-DNA allele was found PMID:31519953
  So no loss-of-function phenotype is described for BEH2 in the cached literature.