Proper telomere length is essential for embryonic stem cell (ESC) self-renewal and pluripotency. Mouse ESCs (mESCs) sporadically convert to a transient totipotent state similar to that of two-cell (2C) embryos to recover shortened telomeres. Zscan4, which exhibits a burst of expression in 2C-like mESCs, is required for telomere extension in these cells. However, the mechanism by which Zscan4 ex...

Simultaneous measurements of cellular DNA and RNA as well as estimates of the sensitivity of DNA in situ to denaturation by acid (which correlates with the degree of chromatin condensation) and cell ability to incorporate 5-bromodeoxyuridine (BUdR), performed on over 40 different cell systems enabled us to subclassify cells into 12 functionally distinct cell cycle compartments. Quiescent cells ...

Top, tree or Egyptian onion, Allium x proliferum (Moench) Schrader, 2n=2x=16, is a minor, vegetatively propagated garden crop in Europe, North America and North East Asia. Several clones of the top onion were found to be locally cultivated in the region of South Croatia under the name “Ljutika-talijanka”. One of these, clone Biorina, was studied by means of both classi­ cal cytogenetic techniqu...

Relative quantities of DNA in individual nuclei of stem and leaf epidermal cells of Arabidopsis were measured microspectrofluorometrically using epidermal peels. The relative ploidy level in each nucleus was assessed by comparison to root tip mitotic nuclei. A clear pattern of regular endopolyploidy is evident in epidermal cells. Guard cell nuclei contain levels of DNA comparable to dividing ro...

5-Fluorouracil (5-FUra) inoculated i.p. into Ehrlich ascites tumor (EATU)-bearing mice inhibited in vivo tumor cell prolif eration and generated a population of EATU cells with half their normal content of DNA. The appearance of aberrant (approxi mately 2C) EATU cells from a normally aneuploid (approxi mately 4C) tumor cell line appeared to require a radiosensitive host cell population, since p...

Apricot (Prunus armeniaca L.) is an important fruit crop and member of the Prunus genus Rosaceae family that planted in many temperate regions worldwide. The quality assessed by pomological parameters which can serve as a decisive factor apricot breeding, because introduction new cultivars required. These differ with climate conditions, geographical location or geographic ecological origin. Sim...

5-Fluorouracil (5-FUra) inoculated i.p. into Ehrlich ascites tumor (EATU)-bearing mice inhibited in vivo tumor cell prolif eration and generated a population of EATU cells with half their normal content of DNA. The appearance of aberrant (approxi mately 2C) EATU cells from a normally aneuploid (approxi mately 4C) tumor cell line appeared to require a radiosensitive host cell population, since p...

Genome size (C-value) was measured in four species of Adriatic seagrasses with interphase-peak DNA image cytometry. The estimated 2C-value was 1.5 pg DNA for Zostera noltii (2n = 12), 1.2 pg for Zostera marina (2n = 12), 1.1 pg for Cymodocea nodosa (2n = 28) and 6.2 pg for Posidonia oceanica, using Pisum sativum (2C-value = 8.84 pg) as the calibration standard. Seagrass leaves were fixed in 4% ...