Saeid Tabein, Seyed Ali Akbar Behjatnia,
Volume 3, Issue 2 (9-2014)
Abstract
In addition to the full-length viral DNA genome, various types of smaller specific DNA molecules have been isolated from plants infected by DNA viruses. These DNAs are usually derived from viral genomes by different ways or have non-viral genome sequences. Some of these DNA have no significant effect on the virus cycle and on the incidence and progression of the disease, while some of them inducing the viral disease symptoms. These components that are known as satellite, defective and defective interfering DNAs, depend on helper viruses for replication, encapsidation and movement in plants. Satellites have no significant homology with the helper virus genome. However, they are required for inducing disease symptoms. While defective and defective interfering DNAs exhibit high homology with the genome of helper viruses, only defective interfering DNAs have ability to interfere with virus replication and with disease symptom induction and development. In this paper, the characteristics of these subviral DNAs and the possible mechanisms by which they are generated and transmitted in virus infected plants are discussed.
Saeid Tabein, Seyed Ali Akbar Behjatnia,
Volume 8, Issue 2 (9-2019)
Abstract
Tabein S and Behjatnia SAA (2019) Intracellular interactions of geminiviruses in host plants. Plant Pathology Science 8(2):86-101. DOI:10.2982/PPS.8.2.86
Geminiviruses (Geminiviridae family) with small circular ssDNA genome are encoding just four to seven proteins on virion and complementary-sense strands of their genomes. To have a progressive infection, they are dependent mostly on host cellular machineries and interact with wide range of different host plants factors and processes. Geminiviruses alter the cell cycle in infected plants and they can support replication of viral DNA. They change host gene expression patterns, inhibit cell death pathways, alter macromolecule trafficking and interfere with protein modification to redirect or suppress host defenses and hormones signaling. Geminiviruses encode gene silencing suppressors to interfere with post-transcriptional gene silencing and alter plant DNA methylation and microRNA (miRNA) pathways, often causing developmental abnormalities. Here, the geminiviruses are discussed as one of the most destructive plant viruses and their proteins interactions with host cell factors and pathways are described.
Nadia Mosharaf, Saeid Tabein, Seyed Ali Akbar Behjatnia , Atena Safi,
Volume 9, Issue 1 (3-2020)
Abstract
Mosharaf N, Tabein S, Behjatnia SAA, Safi A (2019) Role of betasatellites in interaction of viruses with plants
. Plant Pathology Science 9(1):78-90. DOI: 10.2982/PPS.9.1.78.
Betasatellites, as begomovirus-dependent small circular single-stranded DNAs, are multifunctional agents that trigger disease symptoms, suppress gene silencing pathways and also interact with various cellular pathways and factors. These subviral elements have a conserved genome organization that encodes only a functional open reading frame on the complementary sense strand βC1. The encoded beta satellite protein affects only the helper begomovirus cycle factor. The small size with a strong promoter sequence and the ability to replace βC1 with foreign genes made beta satellites suspected tools for the investigation of functional genes. As we expand our knowledge of begomovirus / beta satellite complexes and their interactions with host plants, we develop management approaches for the expansion of begomoviral destructive diseases.
