Reaching the limit of cell divisions, a phenomenon referred to as replicative aging, of the yeast Saccharomyces cerevisiae involves a progressive increase in the cell volume. However, the exact relationship between the number of cell divisions accomplished (replicative age), the potential for further divisions and yeast cell volume has not been investigated thoroughly. In this study an increase...

Introduction Stem cells in adult self-renewing tissues Haemopoiesis Epidermis Gastrointestinal epithelium General characteristics of stem cells Asymmetric divisions Predetermined asymmetry Yeast C. elegans What are the mechanisms of predetermined asymmetric divisions? Asymmetry without lineage involvement Stochastic events Stem cell heterogeneity Environmental regulation Conclusions What is the...

In rodents, cortical interneurons originate from the medial ganglionic eminence (MGE) and caudal ganglionic eminence (CGE) according to precise temporal schedules. The mechanisms controlling the specification of CGE-derived interneurons and their role in cortical circuitry are still unknown. Here, we show that COUP-TFI expression becomes restricted to the dorsal MGE and CGE at embryonic day 13....

Dustin and Auerbach7 considered that lymphocytes initially arose from the el)ithelium of the thymus anlage, while Maximow thought they were derived from associated mesenchymal cells.8 In the adult thymus, the lymphocytes would come chiefly from divisions of preexisting lymphocytes and occasionallv from reticular ceIls2,6,M ( which may he either epithelial or mesenchyrnalt’). In the course of ou...

Oriented cell divisions are necessary for the development of epithelial structures. Mitotic spindle orientation requires the precise localization of force generators at the cell cortex via the evolutionarily conserved LGN complex. However, polarity cues acting upstream of this complex in vivo in the vertebrate epithelia remain unknown. In this paper, we show that Dlg1 is localized at the basola...

How eukaryotic genomes are packaged into compact cylindrical chromosomes in preparation for cell divisions has remained one of the major unsolved questions of cell biology. Novel approaches to study the topology of DNA helices inside the nuclei of intact cells, paired with computational modeling and precise biomechanical measurements of isolated chromosomes, have advanced our understanding of m...

Life for all animals starts with a precise 3D choreography of reductive divisions of the fertilized egg, known as cleavage patterns. These patterns exhibit conserved geometrical features and striking interspecies invariance within certain animal classes. To identify the generic rules that may govern these morphogenetic events, we developed a 3D-modeling framework that iteratively infers blastom...

Cell lineage, cell cycle, and cell fate are tightly associated in developmental processes, but in vivo studies at single-cell resolution showing the intricacies of these associations are rare due to technical limitations. In this study on the marine annelid Platynereis dumerilii, we investigated the lineage of the 4d micromere, using high-resolution long-term live imaging complemented with a li...

The precise pathways of memory T-cell differentiation are incompletely understood. Here we exploit transgenic mice expressing fluorescent cell cycle indicators to longitudinally track the division dynamics of individual CD8(+) T cells. During influenza virus infection in vivo, naive T cells enter a CD62L(intermediate) state of fast proliferation, which continues for at least nine generations. A...

The PC3 gene is transiently expressed during neurogenesis in precursor cells of the telencephalic ventricular/subventricular zone, and is rapidly downregulated before cell migration and differentiation. It is thought to have a role in controlling cell proliferation, but its precise function is not known. Here we present evidence that PC3, when overexpressed in vitro by retroviral-mediated gene ...