Successive accumulation of two size classes of viroid-specific small RNA in potato spindle tuber viroid-infected tomato plants.
Like many plant RNA viruses, infection by potato spindle tuber viroid (PSTVd) is known to lead to RNA silencing and a marked reduction in visible disease. To examine the relationship between RNA silencing and this recovery phenomenon in greater detail, we have carried out time-course analyses of viroid-specific small RNA accumulation using several viroid-host combinations. These analyses revealed the presence of two size classes of viroid-specific small RNAs in infected plants, and sequence analysis subsequently demonstrated the presence of a previously undescribed cluster of small RNAs derived primarily from negative-strand PSTVd RNA. Although the clustering patterns were similar, the size distribution of PSTVd small RNAs isolated from symptomatic leaf tissue became more heterogeneous with time. The process by which viroid-specific small RNAs are generated appears to be more complicated than previously believed, possibly involving multiple DICER-LIKE activities, viroid RNA substrates and subcellular compartments.
Machida
Satoru
S
Plant Pathology Laboratory, Faculty of Agriculture and Life Sciences, Hirosaki University, Hirosaki 036-8561, Japan.
Yamahata
Naoki
N
Plant Pathology Laboratory, Faculty of Agriculture and Life Sciences, Hirosaki University, Hirosaki 036-8561, Japan.
Watanuki
Hiromi
H
Plant Pathology Laboratory, Faculty of Agriculture and Life Sciences, Hirosaki University, Hirosaki 036-8561, Japan.
Owens
Robert A
RA
Molecular Plant Pathology Laboratory, Plant Sciences Institute, Beltsville Agricultural Research Center (USDA/ARS), Beltsville, MD 20705, USA.
Sano
Teruo
T
Gene Research Center, Hirosaki University, Hirosaki 036-8561, Japan.|Plant Pathology Laboratory, Faculty of Agriculture and Life Sciences, Hirosaki University, Hirosaki 036-8561, Japan.
D018551:Solanum lycopersicum / Q000821:virology*; D010935:Plant Diseases / Q000821:virology*; D018515:Plant Leaves / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000737:chemistry / Q000378:metabolism*; D012367:RNA, Viral / Q000737:chemistry / Q000378:metabolism*; D013997:Time Factors; D014772:Viroids / Q000235:genetics / Q000378:metabolism*
D034741:RNA, Small Interfering; D012367:RNA, Viral