AP	Apple proliferation
AY-WB	Aster Yellow Witches’ Broom
C. picta	Cacopsylla picta
FDA	Fluorescein diacetate
GFP	Green fluorescent protein
N.	Nicotiana
NES	Nuclear export signal
NLS	Nuclear localization signal
PI	Propidium iodide
P. mali	Candidatus Phytoplasma mali
PME2	Protein in Malus Expressed 2
qPCR	quantitative PCR
SNP	Single nucleotide polymorphism
Y2H	Yeast two-hybrid