Mutation in GNOM causes:
GNOM encodes ARF-GEF controlling formation of COPI-independent transport vesicles that recycle PIN auxin carriers from endosomes to basal and apical plasma membrane domains. Loss-of-function gnom alleles accumulate PINs in intracellular agglomerations, abolish differential auxin maxima at embryo apex and root pole, and disrupt apical-basal axis specification. Resultant embryos display abnormal zygote division, fused collar-like cotyledons, complete loss of axial distinctions, root pole absence, and dwarf stature phenocopying chemical inhibition with NPA. Hence vesicle trafficking machinery tra
Ref: Mayer et al., Development 1993; Gilbert, Developmental Biology, Chap 20: GNOM mutation causes loss of apical-basal polarity.
