Table 1_Multi-genome comparative analysis and VIGS validation suggest that GhMAPKKK5 negatively regulates fruiting branch angle in upland cotton.xls

Fruiting branch angle (FBA) is an important architectural trait, but its molecular regulation remains poorly understood. Here, we compared the MAPK/ERK kinase kinase (MEKK) subfamily across four upland cotton reference genomes and identified 44 MEKK members in each genome.

Genomic positions and coding sequences were broadly conserved, whereas motif analysis distinguished 26 motif-conserved from 18 motif-variable homologous groups. Integrating this classification with phylogenetic relationships and expression differences between accessions with contrasting FBA prioritized GhMAPKKK5 (GhChrD12G0779) for functional analysis. GhMAPKKK5 expression was lower in large-angle accessions than in compact accessions.