Native 434-residue PF is a C-terminal isoform, with intact SIS domains but no catalytic Cys2 and only 40/299 residues of the GATase domain. The complete glutamine-dependent enzyme assertion is removed; broad binding is retained by comparison with isolated human ligand-bound isomerase structures PMID:19059404(https://pubmed.ncbi.nlm.nih.gov/19059404/). Biosynthetic-process rows stay UNDECIDED because noncatalytic contribution is possible but unverified. The exact function paragraph is reviewed separately with NPI and raw metadata preserved.
The Falcon synthesis integrates fly zeppelin genetics, hexosamine-pathway biology and distinction from Gfat2. However, its catalytic summary and domain discussion concern the 694-residue gene product, not the exact 434-residue PF accession. The complete enzyme and developmental evidence therefore inform gene-level context but cannot restore the missing glutaminase domain and catalytic Cys2 in PF. The exact-isoform analysis governs the activity assessment.