Cassava is an important subsistence crop grown only in the tropics, and represents a major source of calories for many people in developing countries. Improvements in the areas of resistance to insects and viral diseases, enhanced nutritional qualities, reduced cyanogenic content and modified starch characteristics are urgently needed. Traditional breeding is hampered by the nature of the crop,...

Transformation-associated recombination (TAR) is a cloning technique that allows specific chromosomal regions or genes to be isolated directly from genomic DNA without prior construction of a genomic library. This technique involves homologous recombination during spheroplast transformation between genomic DNA and a TAR vector that has 5' and 3' gene targeting sequences (hooks). Typically, TAR ...

To date, the insect nodavirus flock house virus (FHV) is the only virus of a higher eukaryote that has been shown to undergo a full replicative cycle and produce infectious progeny in the yeast Saccharomyces cerevisiae. The genome of FHV is composed of two positive-sense RNA segments: RNA1, encoding the RNA replicase, and RNA2, encoding the capsid protein precursor. When yeast cells expressing ...

The DNA, RNA, and protein of apo C-II have been analyzed in a patient with apo C-II deficiency (apo C-IIHamburg). Markedly reduced levels of plasma and intrahepatic C-II apolipoprotein were demonstrated by immunoblotting and immunohistochemical analysis. Northern, slot blot, and in situ hybridization studies revealed low levels of a normal-sized apo C-II mRNA. No major rearrangement of the apo ...

The function of the vacuolar H(+)-ATPase (V-ATPase) enzyme complex is to acidify organelles; this process is critical for a variety of cellular processes and has implications in human disease. There are five accessory proteins that assist in assembly of the membrane portion of the complex, the V(0) domain. To identify additional elements that affect V-ATPase assembly, trafficking, or enzyme act...

The construction of deletion-knockout poxviruses is a useful approach to determining the function of specific virus genes. This protocol is an adaptation of the transient dominant knockout selection protocol published by Falkner and Moss (1990) for use with vaccinia virus. The protocol makes use of the dominant selectable marker Escherichia coli guanine phosphoribosyltransferase (gpt) gene (Mul...

A natural compound from the Red Sea sponge Ircinia sp., 2-hexaprenylhydroquinone (HPH), has been shown to be a general inhibitor of retroviral reverse transcriptases (from HIV-1, HIV-2 and murine leukaemia virus) as well as of cellular DNA polymerases (Escherichia coli DNA polymerase I, and DNA polymerases alpha and beta). The pattern of inhibition was found to be similar for all DNA polymerase...