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1. the entire gaseous envelope surrounding the earth and subject to the earth's gravitational field.
2. the air or climate in a particular place. adj., atmospher´ic.
Symbol for standard atmosphere.
ATMAtaxia telangiectasia mutated. A checkpoint kinase which transduces genomic stress signals to stop cell cycle progression and promote DNA repair, acting via p53, a tumour suppressor protein. Its cognate gene, ATM (see below), is mutated in ataxia telangiectasia, a rare neurodegenerative disease characterised by ataxia telangiectasias, increased chromosome fragility when exposed to ionising radiation and predisposition to lymphomas.
A gene on chromosome 11q22-q23, which encodes a PI3/PI4 cell-cycle checkpoint kinase that phosphorylates, thereby regulating a broad range of downstream proteins—e.g., tumor suppressor proteins p53 and BRCA1, checkpoint kinase CHK2, checkpoint proteins RAD17 and RAD9, and DNA repair protein NBS1.
Abbreviation for standard atmosphere.