Table 1.

Main features of the viroid RNAs imaged by AFM in this work.

Family	Viroid	Length (nt)	Variant RNA analyzed (GenBank acc no.)	Features	[Mg2+] in the folding buffer*
Pospiviroidae	PSTVd	359	PSTVd-ml(+) (U23058.1)	ml (+) RNA, in vitro transcript (IVT)	0
					4
			PSTVd-mc(+) (AJ634596.1)	mc (+) RNA, isolated from infected tissue	4
Avsunviroidae	PLMVd	337	PLMVd-ml(+)wt (AJ005303.1)	ml (+) RNA (wild type), IVT	0
					4
			PLMVd-ml(+)mut	ml (+) RNA (mutant with kissing-loop disrupted), IVT	4
	ELVd	335	ELVd-ml(+) (AJ536613)	ml (+) RNA, IVT	0
					4
			ELVd-ml(-) (AJ536613)	ml (-) RNA, IVT	4

*The folding buffer is composed of 100 mM HEPES pH 7.4 and 100 mM NaCl, either lacking Mg²⁺ or supplemented with 4 mM MgCl₂.