STM review notes

Review scope: Arabidopsis thaliana STM / SHOOT MERISTEMLESS, UniProt Q38874,
At1g62360. Files reviewed: STM-ai-review.yaml, STM-goa.tsv,
STM-uniprot.txt, STM-deep-research-falcon.md, local cached publications
referenced by GOA, and PANTHER family context PTHR11850.

Key synthesis:

• STM is a class I KNOX/TALE homeobox transcription factor. UniProt states it is
  required for shoot apical meristem formation and probably binds the DNA
  sequence 5'-TGAC-3' [file:ARATH/STM/STM-uniprot.txt "Required for shoot
  apical meristem (SAM) formation during embryogenesis"; "Probably binds to the
  DNA sequence 5'-TGAC-3'"].
• STM suppresses differentiation and promotes cell division in the meristem
  independently of WUS PMID:12070094.
• STM contributes to CLV3/stem-cell homeostasis with WUS at later developmental
  stages PMID:12068101.
• STM/KNOXI activity activates cytokinin biosynthesis, including AtIPT7 induction
  and increased cytokinin levels PMID:16139212.
• STM nuclear localization depends on BLH/BELL partner heterodimerization
  PMID:16513846.
• STM trafficking is regulated by FTIP3/FTIP4 and is tied to nuclear recycling,
  plasma membrane localization, and intercellular trafficking [PMID:29742441
  "This facilitates STM recycling to the nucleus"; "STM localizes substantially
  to the plasma membrane, which promotes intercellular trafficking"].
• Generic protein binding rows were not treated as core functions. Targeted
  KNOX-BELL interaction evidence was modified to protein heterodimerization activity; high-throughput generic interaction rows were removed or marked
  over-annotated where they did not add mechanistic STM evidence.
• The RNA-binding GOA row was removed. The accessible PMID:17965274 text supports
  MPB2C as an RNA and HD motif binding protein, and UniProt describes STM RNA
  binding as "By similarity", not direct Arabidopsis STM evidence.