We also performed UDPS on site-directed mutants and clonal dideoxynucleotide (Sanger) sequencing to assess the influence of PCR-induced mutation in RT genes in the highly conserved KKK RT motif spanning codons 64 to 66 in subtype B and C viruses.
Analyses of the somatic mutant allele frequency spectrum and clonal structure revealed that the tumor cells were derived from a single ancestral cell, but that subsequent evolution occurred, leading to two distinct tumor cell subpopulations.
Robust biomarkers of somatic stem cell mutation and mutant clonal expansion may provide cancer surrogates that are useful for risk assessment.
TET2 is a critical regulator of hematopoietic stem cell (HSC) homeostasis, 20 and TET2 mutants induce self-renewal and clonal expansion in hematopoietic stem/progenitor cells in both normal and malignant hematopoiesis.
To ensure that each mutant and control isolate was truly clonal, a second clonal isolation step was performed into 96-well plates to an average of 1 cell/1500 µl (i.e., 1 cell/10 wells).
More frequent cell division during development can result in enhanced fixation of mutations because of the reduced time available for repair of DNA lesions, and clonal expansion of mutant cells gives a larger population of mutants (Slikker et al. 2004).
This should be considered when exploring the role of DNA replication stress in driving the acquisition and clonal dominance of mutant HSCs in aging.
Together, studies in telomerase-deficient mice provided experimental evidence that telomere dysfunction promotes clonal drifts in the pool of tissue stem cells, as well the initiation and clonal dominance of mutant stem cells with large chromosomal abnormalities.
Nevertheless, a significant contribution of progenitor cells and short-term HSCs to clonal expansion of mutant hematopoietic cells should not be excluded at this time, and future studies need to better define the cell type of origin of initiation and clonal dominance of mutant hematopoiesis.
Identification and isolation of the ST3GAL5 and SLC35A2 mutant clonal cells uncover a previously unappreciated differential contribution of gangliosides to intoxication by CTx.
