Indra K. Vasil

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The Viviparous-1 (Vp1) gene of maize is specifically required for expression of the maturation program in seed development. We show that Vp1 encodes a 73,335 dalton protein with no detectable homology to known proteins. An acidic transcriptional activation sequence was identified by fusion to the GAL4 DNA-binding domain. Expression of VP1 in maize(More)
We have developed a method for the accelerated production of fertile transgenic wheat (Triticum aestivum L.) that yields rooted plants ready for transfer to soil in 8–9 weeks (56–66 days) after the initiation of cultures. This was made possible by improvements in the procedures used for culture, bombardment, and selection. Cultured immature embryos were(More)
The unique bread-making characteristic of wheat flour is closely related to the elasticity and extensibility of the gluten proteins stored in the starchy endosperm, particularly the high-molecular-weight glutenin subunits (HMW-GS), which are important in determining gluten and dough elasticity. The quality of wheat cultivars depends on the number and(More)
The Viviparous-1 (Vp1) gene is required for expression of the C1 regulatory gene of the anthocyanin pathway in the developing maize seed. We show that VP1 overexpression and the hormone, abscisic acid (ABA), activate a reporter gene driven by the C1 promoter in maize protoplasts. Cis-acting sequences essential for these responses were localized. Mutation of(More)
A series of vp1 alleles distinguish at least two classes of maturation-related genes that are regulated by the VP1 factor and abscisic acid (ABA). The intermediate vp1-c821708 and vp1-McW alleles have quiescent (non-viviparous) anthocyanin-deficient phenotypes while maintaining significant levels of maturation-specific gene expression in the developing(More)
Immature embryos, inflorescences, and anthers of eight commercial cultivars of Triticum aestivum (wheat) formed embryogenic callus on a variety of media. Immature embryos (1.0–1.5 mm long) were found to be most suitable for embryogenic callus formation while anthers responded poorly; inflorescences gave intermediate values. Immature embryos of various(More)
Embryogenic callus was induced on segments of young leaves of sugarcane (Saccharum officinarum L.) cultured on Murashige and Skoog's medium supplemented with 0.5–3.0 mg/2,4-D, 5% coconut milk and 3–8% sucrose. The fourth and fifth leaves, especially their midrib and sheath regions within 5 cm from the leaf base, were most suitable for the induction of(More)
The relationship between promoter sequences that mediate Viviparous1 (VP1) transactivation and regulation by abscisic acid (ABA) in the wheat Em promoter was investigated using deletion analysis and directed mutagenesis. The Em1a G-box is strongly coupled to VP1 transactivation as well as to ABA regulation; however, the Em promoter includes additional(More)
Molecular analysis of the transgenes bar and gus was carried out over successive generations in six independent transgenic lines of wheat, until the plants attained homozygosity. Data on expression and integration of the transgenes is presented. Five of the lines were found to be stably transformed, duly transferring the transgenes to the next generation.(More)
The Viviparous-1 (VP1) transcriptional activator of maize is required for abscisic acid induction of maturation-specific genes late in seed development leading to acquisition of desiccation tolerance and arrest in embryo growth. Here, we show that VP1 also inhibits induction of the germination-specific alpha-amylase genes in aleurone cells of the developing(More)