It has been long believed that the cyclin-dependent kinase 2 (Cdk2) binds to cyclin E or cyclin A and exclusively promotes the G1/S phase transition and that Cdc2/cyclin B complexes play a major role in mitosis. We now provide evidence that Cdc2 binds to cyclin E (in addition to cyclin A and B) and is able to promote the G1/S transition. This new concept indicates that both Cdk2 and/or Cdc2 can dr

In normal cells, activation of cyclin-dependent kinases (cdks) requires binding to a cyclin and phosphorylation by the cdk-activating kinase (CAK). The Kaposi's sarcoma-associated herpesvirus encodes a protein with similarity to D-type cyclins. This KSHV-cyclin activates CDK6, alters its substrate specificity, and renders CDK6 insensitive to inhibition by the cdk inhibitor p16INK4a. Here we invest

Activation of the cyclin-dependent kinases to promote cell cycle progression requires their association with cyclins as well as phosphorylation of a threonine (residue 161 in human p34(cdc2)). This phosphorylation is carried out by CAK, the Cdk-activating kinase. We have purified and cloned CAK from S. cerevisiae. Unlike CAKs from other organisms, Cak1p is active as a monomer, has full activity wh

Urban resilience to natural and human-induced shocks and stresses has become an important issue in the contemporary world. Several reviews exist on urban resilience, but limited attempts have been made to critically review studies that shed light on determinants of urban resilience in sub-Saharan Africa (SSA). This study synthesizes both peer-reviewed and grey literature on the determinants of urb

The complex flow of liquid metal in evolving metallic foams is still poorly understood due to difficulties in studying hot and opaque systems. We apply X-ray tomoscopy –the continuous acquisition of tomographic (3D) images– to clarify key dynamic phenomena in liquid aluminium foam such as nucleation and growth, bubble rearrangements, liquid retraction, coalescence and the rupture of films. Each ph

Public sector services are complex in relation to many private sector services. For example, public sector services contain non-voluntary service interaction. This area of practice has not been extensively researched to date. In this article, we explore and discuss service interaction in public non-voluntary services targeting children, in order to understand what elements go into value co-creatio

Drought in Australia has widespread impacts on agriculture and ecosystems. Satellite-based Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) has great potential to monitor and assess drought impacts on vegetation greenness and health. Various FAPAR products based on satellite observations have been generated and made available to the public. However, differences remain among these d

AIMS: Neutrophils have both detrimental and beneficial effects in myocardial infarction (MI), but little is known about the underlying pathways. S100A8/A9 is a pro-inflammatory alarmin abundantly expressed in neutrophils that is rapidly released in the myocardium and circulation after myocardial ischaemia. We investigated the role of S100A8/A9 in the innate immune response to MI. METHODS AND RESUL

Cyclin-dependent kinases (Cdks) control the eukaryotic cell cycle by phosphorylating serine and threonine residues in key regulatory proteins, but some Cdk family members may exert kinase-independent functions that cannot easily be assessed using gene knockout approaches. While Cdk2-deficient mice display near-normal mitotic cell proliferation due to the compensatory activities of Cdk1 and Cdk4, t

Fluid therapy is the most important component involved in the stabilization of postrenal azotemia, however there is not yet a consensus about the ideal rate of fluid therapy after relief of urethral obstruction. Fifteen adult cats were divided in two groups: High Rate Group (HRG) and Low Rate Group (LRG). At predetermined time points was assessed venous blood pH, pCO2, pO2, bicarbonate concentrati

Mouse knockouts of Cdk2 and Cdk4 are individually viable whereas the double knockouts are embryonic lethal due to heart defects, and this precludes the investigation of their overlapping roles in definitive hematopoiesis. Here we use a conditional knockout mouse model to investigate the effect of combined loss of Cdk2 and Cdk4 in hematopoietic cells. Cdk2fl/flCdk4-/-vavCre mice are viable but disp

Mammalian oocytes are arrested at the prophase of meiosis I during fetal or postnatal development, and the meiosis is resumed by the preovulatory surge of luteinizing hormone. The in vivo functional roles of cyclin-dependent kinases (Cdks) during the resumption of meiosis in mammalian oocytes are largely unknown. Previous studies have shown that deletions of Cdk3, Cdk4 or Cdk6 in mice result in vi

Comment on: Abdullah C, et al. Cell Cycle 2011; 10:977-88.

After a decade of extensive work on gene knockout mouse models of cell-cycle regulators, the classical model of cell-cycle regulation was seriously challenged. Several unexpected compensatory mechanisms were uncovered among cyclins and Cdks in these studies. The most astonishing observation is that Cdk2 is dispensable for the regulation of the mitotic cell cycle with both Cdk4 and Cdk1 covering fo