Agrobacterium tumefaciens and related Agrobacterium species have been known as plant
pathogens since the beginning of the 20th century. However, only in the past two decades …

Epigenetics is the study of heritable changes in gene expression that occur without a
change in DNA sequence. Epigenetic phenomena have major economic and medical …

Posttranscriptional gene silencing (PTGS) is a nucleotide sequence–specific defense
mechanism that can target both cellular and viral mRNAs. Here, three types of transgene …

Double-stranded (ds) RNA can induce sequence-specific inhibition of gene function in
several organisms. However, both the mechanism and the physiological role of the …

Virus‐induced gene silencing (VIGS) is a recently developed gene transcript suppression
technique for characterizing the function of plant genes. The approach involves cloning a …

Posttranscriptional gene silencing (PTGS) in plants results from the degradation of mRNAs
and shows phenomenological similarities with quelling in fungi and RNAi in animals. Here …

In transgenic and nontransgenic plants, viruses are both initiators and targets of a defense
mechanism that is similar to posttranscriptional gene silencing (PTGS). Recently, it was …

RNA silencing refers to small regulatory RNA-mediated processes that repress endogenous
gene expression and defend hosts from offending viruses. As an anti-host defense …

Double-stranded RNA (dsRNA) has recently been shown to trigger sequence-specific gene
silencing in a wide variety of organisms, including nematodes, plants, trypanosomes, fruit …

The nitrogen compounds nitrate and ammonium are the minerals that plants need in large
quantities and which limit their growth in temperate zones. The nitrate assimilation pathway …