LevureUne levure est un champignon unicellulaire apte à provoquer la fermentation des matières organiques animales ou végétales. Les levures sont employées pour la fabrication du vin, de la bière, des alcools industriels, des pâtes levées, des antibiotiques et d'exhausteurs de goût (les extraits de levure peuvent servir comme agents de sapidité). Le terme « levure » sans spécification peut avoir un emploi générique ou spécifique, dont on vient de donner deux définitions, l'une au singulier et l'autre au pluriel, toutes les deux renvoyant à une classe large d'espèces que la définition spécifie.
Professional degreeA professional degree, formerly known in the US as a first professional degree, is a degree that prepares someone to work in a particular profession, practice, or industry sector often meeting the academic requirements for licensure or accreditation. Professional degrees may be either graduate or undergraduate entry, depending on the profession concerned and the country, and may be classified as bachelor's, master's, or doctoral degrees.
Aurora kinase AAurora kinase A also known as serine/threonine-protein kinase 6 is an enzyme that in humans is encoded by the AURKA gene. Aurora A is a member of a family of mitotic serine/threonine kinases. It is implicated with important processes during mitosis and meiosis whose proper function is integral for healthy cell proliferation. Aurora A is activated by one or more phosphorylations and its activity peaks during the G2 phase to M phase transition in the cell cycle. The aurora kinases were first identified in 1990 during a cDNA screen of Xenopus eggs.
NocodazoleLe nocodazole est une substance qui est capable de provoquer indirectement la dépolymérisation des microtubules en se fixant sur une arginine de la β-tubuline et ainsi bloquer le développement des cellules en phase M de la mitose. Par leur action sur les microtubules, on utilise des agents semblables qui peuvent être utilisés en biologie pour synchroniser une culture cellulaire en mitose (en fin de prophase) mais aussi en médecine pour bloquer les cellules cancéreuses et les amener à l'apoptose.
Mad2Mad2 (mitotic arrest deficient 2) is an essential spindle checkpoint protein. The spindle checkpoint system is a regulatory system that restrains progression through the metaphase-to-anaphase transition. The Mad2 gene was first identified in the yeast S. cerevisiae in a screen for genes which when mutated would confer sensitivity to microtubule poisons. The human orthologues of Mad2 (MAD2L1 and MAD2L2) were first cloned in a search for human cDNAs that would rescue the microtubule poison-sensitivity of a yeast strain in which a kinetochore binding protein was missing.
Nonsense suppressorA nonsense suppressor is a factor which can inhibit the effect of the nonsense mutation. Nonsense suppressors can be generally divided into two classes: a) a mutated tRNA which can bind with a termination codon on mRNA; b) a mutation on ribosomes decreasing the effect of a termination codon. It's believed that nonsense suppressors keep a low concentration in the cell and do not disrupt normal translation most of the time.
Nucleoside triphosphateA nucleoside triphosphate is a nucleoside containing a nitrogenous base bound to a 5-carbon sugar (either ribose or deoxyribose), with three phosphate groups bound to the sugar. They are the molecular precursors of both DNA and RNA, which are chains of nucleotides made through the processes of DNA replication and transcription. Nucleoside triphosphates also serve as a source of energy for cellular reactions and are involved in signalling pathways. Nucleoside triphosphates cannot be absorbed well, so they are typically synthesized within the cell.
