Expression of the entire polyhydroxybutyrate operon of in plants.

Background: Previously we demonstrated that an entire bacterial operon (the PRN operon) is expressible in plants when driven by the Tomato -yellow-leaf-curl-virus (TYLCV) -derived universal vector IL-60.Petroleum-derived plastics are not degradable, and are therefore harmful to the environment. Fermentation of bacteria carrying operons for polyhydroxyalkanoates (PHAs) produces degradable bioplastics which are environmentally friendly.

Expression of an entire bacterial operon in plants.

Multigene expression is required for metabolic engineering, i.e. coregulated expression of all genes in a metabolic pathway for the production of a desired secondary metabolite.

Isolation and characterization of Israeli acute paralysis virus, a dicistrovirus affecting honeybees in Israel: evidence for diversity due to intra- and inter-species recombination.

We report the isolation, purification, genome-sequencing and characterization of a picorna-like virus from dead bees in Israel. Sequence analysis indicated that IAPV (Israeli acute paralysis virus) is a distinct dicistrovirus. It is most homologous to Kashmir bee virus and acute bee paralysis virus.

A universal expression/silencing vector in plants.

A universal vector (IL-60 and auxiliary constructs), expressing or silencing genes in every plant tested to date, is described. Plants that have been successfully manipulated by the IL-60 system include hard-to-manipulate species such as wheat (Triticum duram), pepper (Capsicum annuum), grapevine (Vitis vinifera), citrus, and olive (Olea europaea). Expression or silencing develops within a few days in tomato (Solanum lycopersicum), wheat, and most herbaceous plants and in up to 3 weeks in woody trees.

Reciprocal sequence exchange between non-retro viruses and hosts leading to the appearance of new host phenotypes.

Divergence among individuals of the same species may be linked to positional retrotransposition into different loci in different individuals. Here we add to recent reports indicating that individual variance occurs due to the integration of non-retroviral (potyviral) RNAs into the host genome via RNA recombination followed by retrotransposition. We report that in bees (Apis mellifera), approximately 30% of all tested populations carry a segment of a dicistrovirus in their genome and have thus become virus-resistant.

Occurrence of a DNA sequence of a non-retro RNA virus in a host plant genome and its expression: evidence for recombination between viral and host RNAs.

This study demonstrates that sequences homologous to those of the non-retro RNA virus (Potato virus Y; PVY) are integrated into the genome of several grapevine varieties. The integrated PVY-coat-protein-like cistron is expressed in the grapevine as indicated by Southern and Western blot analyses as well as by RNase protection assay. In addition, genome-walking studies showed that one PVY-like sequence is flanked by 41-bp direct repeats and is embedded in authentic grapevine sequences, flanked by inverted repeats.

ORF 5 of grapevine virus A encodes a nucleic acid-binding protein and affects pathogenesis.

A previous functional analysis of the genome of grapevine virus A (GVA) was not conclusive as to the role of open reading frame 5 (ORF 5). This ORF encodes a 10-kDa protein (p10) carrying two distinct domains: a basic, arginine-rich domain and a zinc-finger domain. P10 was cloned and expressed in Escherichia coli, and was shown by northwestern assays to interact with nucleic acids.

Identification and characterization of phytoplasmal genes, employing a novel method of isolating phytoplasmal genomic DNA.

Phytoplasmas are unculturable, insect-transmissible plant pathogens belonging to the class Mollicutes. To be transmitted, the phytoplasmas replicate in the insect body and are delivered to the insect's salivary glands, from where they are injected into the recipient plant. Because phytoplasmas cannot be cultured, any attempt to recover phytoplasmal DNA from infected plants or insects has resulted in preparations with a large background of host DNA.

Vaccination with E. coli recombinant empty viral particles of infectious bursal disease virus (IBDV) confer protection.

The A genome segment of the highly virulent Infectious bursal disease virus (IBDV) was amplified using long and accurate-RT-PCR (LA-RT-PCR). The entire sequence region encoding VP2, VP4, and VP3 in that order was cloned and sequenced. Following subcloning into the Escherichia coli expression vector pET21a under the T7 promoter, viral proteins were expressed and processed as demonstrated by Western blot analysis.