in this study, for the first time in iran, the karyotype of bigmouth lotak, cyprinion macrostomum heckel, 1843, was investigated through examining metaphase chromosomes of seven fish with mean weight 30±5g caught by electrofishing from godarkhosh river in ilam province. to stimulate cell divisions, fish were injected intraperitoneally two times by phytohemagglutinin (pha). the cell divisions we...

Asymmetric division is an important property of stem cells. In Caenorhabditis elegans, the Wnt/beta-catenin asymmetry pathway determines the polarity of most asymmetric divisions. The Wnt signalling components such as beta-catenin localize asymmetrically to the cortex of mother cells to produce two distinct daughter cells. However, the molecular mechanism to polarize them remains to be elucidat...

Human neural progenitor cells (hNPCs) can be recovered from postmortem human brains and used to study the molecular basis of neurogenesis. Human NPCs are being used to investigate the molecular basis of cell fate determination during stem cell divisions, based on comparison with the Drosophila model system. Drosophila neuroblasts and sensory organ precursors undergo well-defined asymmetric cell...

Asymmetric cell division plays a fundamental role in generating various types of embryonic cell. In ascidian embryos, asymmetric cell divisions occur in the vegetal hemisphere in a manner similar to those found in Caenorhabditis elegans. Early divisions in embryos of both species involve inductive events on a single mother cell that result in production of daughters with different cell fates. H...

Drosophila neural stem cells or neuroblasts undergo typical asymmetric cell division. An evolutionally conserved protein complex, comprising atypical protein kinase C (aPKC), Bazooka (Par-3) and Par-6, organizes cell polarity to direct these asymmetric divisions. Aurora-A (AurA) is a key molecule that links the divisions to the cell cycle. Upon its activation in metaphase, AurA phosphorylates P...