RNAi-Mediated Resistance to Bean golden mosaic virus in Genetically Engineered Common Bean (Phaseolus vulgaris)

Abstract

Bean golden mosaic virus (BGMV) is transmitted by the whitefly Bemisia tabaci in a persistent, circulative manner, causing the golden mosaic of common bean (Phaseolus vulgaris L.). The characteristic symptoms are yellow-green mosaic of leaves, stunted growth, or distorted pods. The disease is the largest constraint to bean production in Latin America and causes severe yield losses (40 to 100%). Here, we explored the concept of using an RNA interference construct to silence the sequence region of the AC1 viral gene and generate highly resistant transgenic common bean plants. Eighteen transgenic common bean lines were obtained with an intron-hairpin construction to induce post-transcriptional gene silencing against the AC1 gene. One line (named 5.1) presented high resistance (approximately 93% of the plants were free of symptoms) upon inoculation at high pressure (more than 300 viruliferous whiteflies per plant during the whole plant life cycle) and at a very early stage of plant development. Transgene-specific small interfering RNAs were detected in both inoculated and non-inoculated transgenic plants. A semiquantitative polymerase chain reaction analysis revealed the presence of viral DNA in transgenic plants exposed to viruliferous whiteflies for a period of 6 days. However, when insects were removed, no virus DNA could be detected after an additional period of 6 days.

Banana bunchy top disease (BBTD) symptom expression in banana and strategies for transgenic resistance: A review

“…PTGS used in the development of resistance against the viruses ACMV (Vanitharani et al, 2003, Vanderschuren et al, 2007, mungbean yellow mosaic virus (MYMV) (Pooggin et al, 2003), Sri Lankan cassava mosaic virus (SLCMV), East African cassava mosaic virus (EACMV) , TYLCV (Abhary et al, 2006, Fuentes et al, 2006Zrachya et al, 2007), bean golden mosaic virus (BGMV) (Bonfim et al, 2007), and TLCV (Ramesh et al, 2007). Although only in its early stages, research utilizing this process to achieve virus resistance is very promising in that any viral coding or noncoding sequences can be targeted and no protein need be expressed.…”

Diversity among isolates of cowpea severe mosaic virus infecting cowpeas in northeastern Brazil

“…The samples were incubated for 30 min at 60°C and kept on ice until transfer to a nylon membrane. Hybridization was carried out as described elsewhere (Bonfim et al, 2007). The probe was obtained from the Taíba-CE CPSMV isolate cloned into the pGEMT Easy Vector (Promega) and digested with EcoRI and HindIII to generate a 165-bp fragment.…”

“…An attractive strategy would be to use engineered transgenic plants with the RNA interference (RNAi) concept to silence viral genes (Bonfim et al, 2007). The use of inverted repeat constructs, which result in double-stranded RNA transcripts, is the most efficient means of generating transformed lines showing effective gene knockdown or virus resistance (Aragão and Faria, 2009).…”

Artificial trans-acting small interfering RNA: a tool for plant biology study and crop improvements

“…In addition to plant biology studies, RNAi plays important and unique roles in crop genetic improvements (Auer and Frederick 2009;Baykal and Zhang 2010). RNA interference may achieve more significant crop improvements than conventional breeding, as illustrated by various important crop species with different improved traits (Liu et al 2002;Ogita et al 2003;Gilissen et al 2005;Le et al 2006;Bonfim et al 2007;Shi et al 2007;Dodo et al 2008;eady et al 2008;Flores et al 2008;Shimizu et al 2009). Many of these studies show that the RNAi-mediated silencing is inheritable, alleviating long-standing concerns about the RNAi inheritability.…”