The repetitive DNA sequences of the newt, Triturus viridescens, have been studied by nucleic acid hybridization procedures. Complementary RNA was synthesized enzymatically from unfractionated newt DNA. This RNA hybridized strongly to the centromeric regions of both somatic and lampbrush chromosomes It also bound to other loci scattered along the lengths of the chromosomes The amplified ribosoma...

Absorption measurements in violet light (lambda 4047 A) of thin sections of mature newt erythrocytes have indicated the presence of a haem compound, probably haemoglobin, within the chromosomal regions of the nucleus. The amount is about 45 per cent of that in the cytoplasm. The possible significance of this nuclear haemoglobin in determining nuclear structure is discussed in terms of the elect...

Digit regeneration has been examined in Triturus cristatus. Because of their size, blastemas that form after digit amputation are relatively a lot more suitable for quantitative studies that involve for example the counting of cells in histological sections. They are also very useful for the study of some basic histological aspects of regeneration particularly cartilage formation. This has been...

THE skins of many vertebrates react to variations in the amount of hormones of the endocrine glands, especially of the thyroid and pituitary. Moulting in Triturus viridescens is inhibited after both thyroidectomy and hypophysectomy or both operations simultaneously performed. The cornified layers continue to form and the accumulation of these makes the animal appear grimy (Adams and Richards, 1...

In a survey of several mammalian genomes, namely humans, rodents and bovines, the differences in the 5-methylcytosine (m5C) content show that repeated DNA sequences from sperm were undermethylated and from various somatic tissues were heavily methylated. This report shows a pattern of methylation in male newt (Amphibia, Urodela) Triturus cristatus carnifex (T. c. c.) unlike that so far describe...

Cytological changes in thyroid glands following administration of thyroid-stimulating hormone (TSH), were studied in adult salamanders, Ambystoma tigrinum, Triturus torosus, and Triturus viridescens by electron and light microscopy. Thyroids from untreated salamanders contained large follicles, faintly basophilic colloid, low follicle cells with flattened nuclei, and scant, slightly basophilic ...