Publications by authors named "Tamara Mclennan"

The tendency of 5-methylcytosine (5mC) to undergo spontaneous deamination has had a major role in shaping the human genome, and this methylation damage remains the primary source of somatic mutations that accumulate with age. How 5mC deamination contributes to cancer risk in different tissues remains unclear. Genomic profiling of 3 early-onset acute myeloid leukemias (AMLs) identified germ line loss of MBD4 as an initiator of 5mC-dependent hypermutation.

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Mutations of the reelin gene cause severe defects in cerebral cortex development and profound intellectual impairment. While many aspects of the reelin signaling pathway have been identified, the molecular and ultimate cellular consequences of reelin signaling remain unknown. Specifically, it is unclear if termination of reelin signaling is as important for normal cortical neuron migration as activation of reelin signaling.

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DiGeorge syndrome, caused by a 22q11 microdeletion or mutation of the TBX1 gene, varies in severity greatly, even among monozygotic twins. Epigenetic phenomena have been invoked to explain phenotypic differences in individuals of identical genetic composition, although specific chromatin modifications relevant to DiGeorge syndrome are elusive. Here we show that lack of the histone acetyltransferase MOZ (MYST3/KAT6A) phenocopies DiGeorge syndrome, and the MOZ complex occupies the Tbx1 locus, promoting its expression and histone 3 lysine 9 acetylation.

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During prenatal development, a large number of different cell types are formed, the vast majority of which contain identical genetic material. The basis of the great variety in cell phenotype and function is the differential expression of the approximately 25,000 genes in the mammalian genome. Transcriptional activity is regulated at many levels by proteins, including members of the basal transcriptional apparatus, DNA-binding transcription factors, and chromatin-binding proteins.

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