CLV2/FEA2-family functions (regulation of meristem development, flower development) are propagated across the PANTHER PTN009226978 phylogenetic group by IBA.

SwissProt keyword-derived (SPKW) annotations were present in the Sept 2025 goa_uniprot_gcrp snapshot but removed from the current GOA release after GOA retired the keyword2GO pipeline for cellular organisms.

For FEA2, the keyword "Differentiation" mapped to the over-broad term "cell differentiation" (GO:0030154); the precise biology is meristem-size/stem-cell homeostasis, better captured by meristem-maintenance / meristem-growth terms.

The UniProt subcellular-location keyword "Cell membrane" (SL-0039) maps to plasma membrane (GO:0005886); confirmed experimentally by FEA2-GFP localization.

fea2, a transposon-tagged maize mutant, causes massive overproliferation of the ear inflorescence meristem and a more modest enlargement of floral meristems with increased organ number; FEA2 normally functions in these meristems to restrict growth.

FEA2 encodes a membrane-localized LRR receptor-like protein most closely related to Arabidopsis CLAVATA2 (CLV2); the CLAVATA pathway for regulation of meristem size is functionally conserved throughout the angiosperms.

FEA2-GFP localizes to the plasma membrane, supporting the hypothesis that FEA2 acts as a receptor for an extracellular ligand; FEA2 has no obvious intracellular signaling domain and likely acts as part of a heterodimeric receptor.

fea2 maps to a QTL for seed row number, linking FEA2-mediated meristem-size control to maize ear architecture and potential crop-yield improvement.

Weak/quantitative FEA2 alleles (mutagenesis of Gly-332, Met-367, Gly-405, Pro-477) give no fasciation but increased kernel row number / larger inflorescence meristems, establishing FEA2 as a quantitative regulator of maize KRN.

FEA2 is the maize CLAVATA2 (CLV2) ortholog, a plasma-membrane LRR receptor-like protein that perceives CLE peptides to restrict stem-cell proliferation and meristem size, preventing ear fasciation; it is not an enzyme or transporter.

FEA2 is a signal-routing receptor hub - it transmits the ZmCLE7 (maize CLV3 ortholog) signal through the heterotrimeric G-protein alpha subunit CT2 (COMPACT PLANT2) and the ZmFCP1 signal through the membrane pseudokinase ZmCRN (CORYNE); fea2 mutants are resistant to both peptides, placing FEA2 upstream of both branches.

CLE-peptide perception by FEA2 complexes ultimately represses the WUSCHEL ortholog ZmWUS1, consistent with the conserved CLV-WUS negative-feedback logic that restricts meristem size; loss of function enlarges meristems and increases kernel row number (KRN), making FEA2 a breeding-relevant target for ear architecture.

Co-IP and BiFC support a direct FEA2-ZmCRN interaction and a (possibly indirect) FEA2-CT2 association, consistent with two distinct FEA2-containing receptor complexes rather than one static assembly.