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The microphthalmia-associated transcription factor, Mitf, is identified as a novel regulator of the DIAPH1 gene encoding the diaphanous-related formin Dia1 that controls actin polymerization. The results have implied that the variations in the repertoire of environmental cues that determine Mitf activity would dictate the differentiation, proliferative and invasive/migratory potential of melanoma cells through a dynamic epigenic mechanism.

The p63 function is investigated in a post-developmental context by using siRNAs that are directed against p63 to down-regulate p63 expression in regulating human epidermis. The results have indicated that p63 is required for both the proliferative and differentiation potential of developmentally mature keratinocytes.

A review of experiments that provides coordination and communication between p53-IGF-1-AKT-TOR pathways is presented. The results showed that these pathways regulate cell growth, proliferation and death that are central to our understanding and variety of physiological and pathological conditions, including cancer, diabetes and longevity.

A study shows that the adult mammalian cardiomyocytes cells can divide and the p38 MAP kinase activity is the important mechanism used by mammalian cardiomyocytes to control cell cycle. The findings of the study establish that p38 is the key negative regulator of cardiomyocyte proliferation indicating that adult cardiomyocytes can divide.

The Drosophila Sterile-20 kinase Slik promotes tissue growth during development by stimulating cell proliferation and by preventing apoptosis. It is observed that Slik acts via distinct pathways to coordinate cell proliferation with epithelial cell behavior during tissue growth.

Research has been conducted on stem and cancer cells. Results demonstrate that nucleostemin controls stem and cancer cell prolioferation.

Control of Drosophila eye development by teashirt, eyeless, and homothorax, in concert, has been studied. Several subdomains along the anterior-to-posterior axis of the eye disc are defined. The combination of transcription factors may play at least two eye development roles, blocking the expression of later-acting transcription factors in the eye development cascade and promoting cell proliferation. Two homeobox genes, eyeless (ey) and homothorax (hth), and the zinc-finger gene, teashirt (tsh), are expressed by a subdomain anterior to the morphogenetic furrow (MF).

A homeobox gene, PRESSED FLOWER (PRS), has been found to be very likely to regulate lateral axis-dependent development of Arabidopsis flowers. A flower mutant of Arabidopsis, pressed flower (prs), has been isolated and analyzed. The phenotype of prs has been found and the molecular identification of PRS has been carried out. This is the first report of a gene involved in the lateral axis-dependent development of lateral organs and floral meristems of Arabidopsis.

Multiple Ras-dependent phosphorylation pathways have been found to regulate Myc protein stability. Two N-terminal phosphorylation sites in Myc , Thr 58 and Ser 62 were investigated. A synergistic role for multiple Ras-mediated phosphorylation pathways in the control of Myc protein accumulation during the first stage of cell proliferation has been defined.

A novel beta-catenin-interacting protein, ICAT, has been identified. It has been found to inhibit interaction of beta-catenin with TCF-4 and represses beta-catenin-TCF-4-mediated transactivation. ICAT inhibits Xenopus axis formation in that it interferes with Wnt signaling. It appears likely that ICAT negatively regulates Wnt signaling by inhibition of the interaction of beta-catenin with TCF. It is also integral in development and cell proliferation.

Antiapoptotic activity of Stat5 has been shown to be required in end stages of myeloid differentiation. Chicken myeloblasts that express dominant-negative Stat5 alleles and hematopoietic cells from Stat5-deficient mice have been used to study the role of Stat5 in survival, proliferation and differentiation of primary myelomonocytic cells. Absence of functional Stat5 brings lower doubling times and lack of cytokine-dependent protection from apoptotic death in cell differentiation. It seems bcl-x has an antiapoptotic Stat5 target gene. Stat5 may help in survival and proliferation of differentiating myeloid progenitor cells when stress/pathological circumstances such as inflammation prevail.

Results demonstrate that Drosophila phosphate and tensin homolog (DPTEN) protein controls cell number and size and mediates subcellular organization of the actin cytoskeleton. Data further indicate that DPTEN modulates tissue mass by inhibiting a protein kinase and the insulin receptor substrate homolog Chico.

Basic helix-loop-helix (bHLH) protein PTF1-p48 appears to be needed for differentiation and/or proliferation of the cell lineage for the exocrine pancreas. A mouse with a null mutation of the p48 allele does not have any exocrine pancreatic tissue or associated products. The exocrine pancreas seems to be necessary for the endocrine pancreas to be assembled correctly. When the exocrine pancreas is absent, cells migrate to the spleen instead.

The transcription factor CREM (cAMP-responsive promoter element modulator) apparently regulates the proliferation of hepatocytes during liver regeneration. A 10-hr delay in the cell proliferation wave occurs when CREM is lacking in mice that have undergone partial hepatectomy. DNA synthesis, mitosis and phosphorylated histone H-3 positive cells are reduced. Deregulation of the expression of cyclins A, B, D1, E, and cdc2, and of c-fos and tyrosine aminotransferase also occurs.

Via a signaling pathway that involves the tumor suppressor p19ARF and retinoblastoma protein, the adenovirus E1A oncogene activates p53. It can be seen that p19 is part of a p53-dependent failsafe system to stop rampant cell proliferation. There are synergistic effects for p19ARF and DNA damage pathways in inducing p53 and they may help E1A's contribution to chemo- and radiosensitivity.

Ovarian and mammary gland transplants were performed with C/EBP-beta (CCAAT-enhancer binding protein) deficient mice. C/EBP-beta-deficient epithelium development was defective in a wild-type stroma and host background. C/EBP-beta is cell-autonomous in its role in the proliferation and differentiation of mammary secretory epithelial cells. It plays an essential role in activating milk protein genes.

Morphogenesis of the Malpighian tubules in insects is controlled in Drosophila by the 'tip cell,' which is one large cell. Seven-up is an important component induced by mitogenic epidermal growth factor (EGF) receptor signaling from the tip cell. Seven-up can then regulate transcription of regulators of the cell cycle. The tip cell has been thought to send a mitogenic signal that brings on division in close-by cells. Seven-up is a homolog of the human transcription factor COUP-TF.

The inhibition of proliferation and medulloblastoma (MB) cells by several different bone morphogenic proteins (BMPs) is discussed. The analysis shows that BMPs lead to the post-transcriptional down-regulation of Math1 (Atoh1), which ultimately leads to the discussed suppression.

Several conditional gene targeting studies are conducted to explain the different cellular activities of prohibitions that consist of a conserved family of membrane proteins. The prohibitions are found to effectively control the cell proliferation and apoptosis by regulating the OPA1-dependent cristae morphogenesis in mitochondria.

Hippo signaling pathway plays an important role in controlling organ size by restricting both cell proliferation and apoptosis in Drosophila. Study is conducted to show that in mammalian cells, the transcription coactivator Yes-associated protein (YAP) is inhibited by cell density via the Hippo pathway.

A study examined the role of SIRT1 during vascular blood vessel growth and its control on the angiogenic activity of endothelial cells. The findings revealed that SIRT1 acts as a modulator of endothelial gene expression governing postnatal vascular growth.

A study was undertaken to observe the Notch pathway that is a regulator of cell features in metazoan organisms. Results showed that the Notch pathway Delta-like 4 were important in human pathological conditions and might be useful in cancer treatment.

Study is conducted to show that early mitotic inhibitor (Emil) plays an important function in cell proliferation by preventing rereplication. Results suggest that an essential function of Emil in S and G2 cells is to prevent rereplication via stabilization of inhibitors of rereplication of such as cyclin A and geminin.

A study shows that sustained Notch activity is required for the temporal maintenance of specific cohorts of proliferating progenitors, which underlies the ability to specify late-arising cell lineages during pituitary organogenesis. It is learnt that sustained signaling in progenitor cells is required to prevent conversion of the late-arising cell lineages to early-born cell lineages, permitting specification of diverse cell types, a strategy likely to be widely used in mammalian organogenesis.

A reversibly switchable mouse transgenic model of Myc-dependent Beta-cell carcinogenesis is used to delineate the kinetics and causal sequence of angingenic processes following acute Myc activation. It is shown that the onset of endothelial cell proliferation is induced shortly after Myc-induced cell cycle entry of beta cells.

The identification of E4F1, an inhibitor of cellular proliferation is reported as a new BMI1-interacting partner in hematopoietic cells. This proves that Bmi1 and E4f1 genetically work together in hematopoietic compartment to control cellular proliferation and that E4F1 is the main modulator of BMI1activity in primitive hematopoietic cells.

Study is conducted to show that depletion of GW182 leads to changes in mRNA expression profiles indicating that GW182 is a genuine component of miRNA pathway and that GW182 triggers silencing of bound transcripts by inhibiting protein expression and promoting mRNA decay via a deadenylation and decapping mechanism. Evidence is also provided to show that mRNA degradation by miRNAs requires GW182, the CCR4:NOT dedenylase, and the DCP1:DCP2 decapping complexes.

Generation of the spinal cord relies on proliferation of undifferentiated cells located in a caudal stem zone and a study was conducted to know how fibroblast growth factor (FGF) signaling controls cell behavior. The findings suggest a mechanism for the establishment of the cell selection process, lateral inhibition, mutual inhibition between Delta/Notch-expressing stem zone cells switchers to single Deltal-presenting neurons as FGF activity declines in the newly formed neuroepithelium.

A study shows that TAF4b, a transcriptional regulator is required for maintenance of spermatogenesis in the mouse. The data obtained from the studies carried out on the TAF4b indicate that it is required for the precise expression of gene products essential for germ cell proliferation.

E2F that directly participates in the transcriptional control of Arf in both normal and transformed cells is shown. It is proposed that monitoring of E2F levels and activity is a key component of Arf's ability to respond to inappropriate, but not cellular proliferation.

Normal hepatocytes that escape negative control of proliferation lead to tumor cells. Activation of the PI3K/Akt pathway in live tumor cells block the growth inhibitory activity of C/EPP alpha.

Findings reveal that pathways of gene activity are linked in mammals via p53 to mechanisms controlling cell proliferation. The importance of appropriate expression of the short and long p53 isoforms in lengthening the mammalian life spans is highlighted.

Cell proliferation is deregulated by expression of adenovirus to facilitate DNA replication by quick initiation of apoptosis signaled through proapoptotic BAK in productively infected cells. BAK is complexed with the anti-apoptotic BCL-2 family member Myeloid Cell Leukemia 1 (MCL-1) in uninfected cells.