Albinism in plants is characterized by partial or complete loss of chlorophyll pigments and incomplete differentiation chloroplast membranes. This a very common problem encountered interspecific crosses tissue culture experiments including anther generation doubled haploids. impairs photosynthesis the eventually die at young stage without reaching maturity. Environmental conditions such as ligh...

Cultivated and wild potato species synthesize a wide variety of steroidal glycoalkaloids (GAs). During breeding programs, species genomes are often put together through either sexual or somatic hybridization. Therefore, the determination of the GA composition of hybrids is very important in that it may affect either human consumption, or resistance to pathogen and pests. Here, we report the res...

Cellular responses to environmental stimuli require conserved signal transduction pathways. In budding yeast (Saccharomyces cerevisiae), nutrient limitation induces morphological changes that depend on the protein kinase A (PKA) pathway and the Kss1 mitogen-activated protein kinase (MAPK) pathway. It was unclear to what extent and at what level there is synergy between these two distinct signal...

Mouse spermatozoa were treated with trypaflavine, toluidine blue or nitrogen mustard before fertilization in attempts to destroy the sperm chromosomes and so induce haploid gynogenetic development of the egg. High concentrations of either chemical decreased the activity of spermatozoa. Trypaflavine and toluidine blue had a photodynamic action on spermatozoa and lowered the fertilization rate; n...

Chromosomal rearrangements can result from crossing over during ectopic homologous recombination between dispersed repetitive DNA. We have previously shown that meiotic ectopic recombination between artificially dispersed ade6 heteroalleles in the fission yeast Schizosaccharomyces pombe frequently results in chromosomal rearrangements. The same recombination substrates have been studied in mito...

A new type of radiation-sensitive mutant of S. cerevisiae is described. The recessive radH mutation sensitizes to the lethal effect of UV radiations haploids in the G1 but not in the G2 mitotic phase. Homozygous diploids are as sensitive as G1 haploids. The UV-induced mutagenesis is depressed, while the induction of gene conversion is increased. The mutation is believed to channel the repair of...