Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2002 Dec;76(24):13094-6.
doi: 10.1128/jvi.76.24.13094-13096.2002.

Two chloroplastic viroids induce the accumulation of small RNAs associated with posttranscriptional gene silencing

A E Martínez de Alba  1 , R Flores, C Hernández
Affiliations

Two chloroplastic viroids induce the accumulation of small RNAs associated with posttranscriptional gene silencing

A E Martínez de Alba et al. J Virol. 2002 Dec.

Abstract

In plants, posttranscriptional gene silencing (PTGS) has been reported for cytoplasmic RNAs from endogenous nuclear genes, transgenes, viruses, and, recently, for a viroid with nuclear replication and accumulation. However, phenomena of this kind have not been described for mitochondrial or chloroplastic RNAs. Here we show that viroids that replicate and accumulate in the chloroplast are also targets of PTGS and this process may control viroid titer.

PubMed Disclaimer

Figures

FIG. 1.
FIG. 1.
Detection by Northern blot analysis of the PLMVd-specific small RNAs associated with PTGS. Nucleic acid preparations from healthy (H) and PLMVd-infected (I) peach leaves were separated in a 15% denaturing polyacrylamide gel and hybridized with positive- and negative-sense radioactive riboprobes derived from the “left” (A) and “right” (B) parts of the PLMVd molecule as indicated by thick lines on the schematic representation of the PLMVd secondary structure shown below the panels. Positions of the 24- and 20-mer DNA markers are at the right, and the signals corresponding to the small RNAs are indicated by an arrowhead at the left. The bands visible in the upper part of the gel are mainly generated by unit- and shorter-than-unit-length PLMVd RNAs.
FIG. 2.
FIG. 2.
Detection by Northern blot analysis of the CChMVd-specific small RNAs associated with PTGS. Nucleic acid preparations from leaves of healthy (H) chrysanthemum plants and those infected with a nonsymptomatic (NS) or a symptomatic (S) strain of CChMVd were separated in a 15% denaturing polyacrylamide gel and hybridized with full-length radioactive riboprobes for the detection of positive and negative viroid strands. Positions of the 24- and 20-mer DNA markers are at the right, and the signals corresponding to the small RNAs are indicated by an arrowhead at the left. The bands visible in the upper part of the gel lanes containing the infected extracts are mainly generated by unit- and shorter-than-unit-length CChMVd RNAs. The weak signals observed in the upper part of the gel lanes containing the healthy extracts result from nonspecific hybridization.
FIG. 3.
FIG. 3.
Northern blot analysis to search for the viroid-specific small RNAs associated with PTGS in nucleic acid preparations from leaves of avocado plants. Preparations from healthy (H) and ASBVd-infected (I) samples were separated in a 15% denaturing polyacrylamide gel and hybridized with full-length radioactive riboprobes for the detection of positive and negative viroid strands. Positions of the 24- and 20-mer DNA markers are at the right. The bands visible in the upper part of the gel are generated by unit-, shorter-than-unit, and longer-than-unit-length ASBVd RNAs.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Anandalakshmi, R., R. Marathe, X. Ge, J. M. Herr, Jr., C. Mau, A. Mallory, G. Pruss, L. Bowman, and V. B. Vance. 2000. A calmodulin-related protein that suppresses posttranscriptional gene silencing in plants. Science 290:142-144. - PubMed
    1. Baulcombe, D. C. 2002. RNA silencing. Curr. Biol. 12:R82-R84. - PubMed
    1. Cogoni, C., and G. Macino. 2000. Post-transcriptional gene silencing across kingdoms. Curr. Opin. Genet. Dev. 10:638-643. - PubMed
    1. De la Peña, M., B. Navarro, and R. Flores. 1999. Mapping the molecular determinant of pathogenicity in a hammerhead viroid: a tetraloop within the in vivo branched RNA conformation. Proc. Natl. Acad. Sci. USA 96:9960-9965. - PMC - PubMed
    1. Flores, R., J. W. Randles, M. Bar-Joseph, and T. O. Diener. 2000. Subviral agents: viroids, p. 1009-1024. In M. H. V. van Regenmortel et al. (ed.), Virus taxonomy, 7th Report of the International Committee on Taxonomy of Viruses. Academic Press, San Diego, Calif.

Publication types