Therefore, this new structure should be used from now on as reference for future experimental and computational folding studies as well as for the interpretation of gpW’s biological function. Aurora kinases belong to a conserved family of serine/threonine kinases that are pivotal to the successful execution of cell division. Three Aurora kinases, which share sequence homology in their central catalytic kinase domains, have been identified in mammals. Yeast genome encodes only one memberIpL1 of this kinase family, but there are two members of this family in Drosophila. The three members of the mammalian family, besides being implicated as mitotic regulators, have generated significant interest in the cancer research field due to their elevated expression profiles detected in many human cancers. Aurora-A is ubiquitously expressed especially in tissues with high mitotic and meiotic index. Aurora-A mRNA, protein expression levels and kinase activity are cell cycle regulated, low in G1/S phase, peaking in G2/M and then dropping upon mitotic exit into the next G1. Aurora-A displays dynamic subcellular localization: from duplicated centrosomes at the end of S phase to mitotic spindle poles from prophase through telophase. Activation of centrosomal Aurora-A at late G2 phase is essential for centrosome maturation and mitotic entry. Its further activation are required for centrosome separation, leading to subsequent bipolar spindle formation and chromosomal alignment. Aurora-A is found overexpressed in a large number of tumours. Aurora-A is an oncogene. It induces tumour formation when NIH-3T3 or Rat1 cells overexpressing Aurora-A are injected in nude mice. Aurora-B expression peaks at G2/M phase and the maximum kinase activity is reached at transition during metaphase to anaphase. Aurora-B is responsible for histone H3 phosphorylation on both Ser-10 and Ser-28 during mitosis. Aurora-B is also required to correct syntelic attachments of chromosomes and is essential for cytokinesis. Unlike Aurora-A and -B, which are ubiquitously expressed in many tissues, particularly in mitotically dividing cells, Aurora-C is predominantly expressed in the testis and in meiotically dividing gametes where it is associated with INCENP in spermatocytes. Aurora-C is, however, found at a low level in other tissues. Aurora-C directly competes with Aurora-B for binding to INCENP and survivin. Overexpression of Aurora-C in cancerous tissues and cell lines also raises questions about its potential role in carcinogenesis and its effect on the proliferative capacity of tumour cells. Here we asked whether Aurora kinase C has any oncogene activity. We found that Aurora kinase C causes both centrosome amplification and multinucleation and also has the capability to transform NIH-3T3 cells when overexpressed. Furthermore, we show that NIH-3T3 cells overexpressing Aurora kinase C promote tumour formation when injected into nude mice. Hence, we provide evidence that Aurora-C is a proto-oncogene. White adipose tissue is a major endocrine organ and secretes various bioactive proteins – the adipokines – which are involved in GW786034 different physiological processes.
In obesity adipose tissue hypoxia was suggested to be involved in the dysregulation of adipokine expression
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