The absence of additional expressing cells for the C-terminal translational fusion is also consistent with ceh-19a not adding to the expression arising from ceh-19b.
A more restrictive constraint coming from the EARSM expression arises compared to a classical eddy viscosity model.
The latter finding could indicate that perturbed expression arises at the posttranscriptional level since microRNAs of the cluster are assumed to derive from a single precursor transcript., Further examples of aberrant expression of microRNAs from this imprinting cluster in cancer are provided in Table S1.
Once imprinted gene expression arises, the kinship or parental conflict theory of imprinting (Haig, 2013) posits that it could be evolutionarily selected because asymmetrically related kin (e.g., half-siblings that have the same mother but different fathers) compete for maternal resources.
Consequently, if the CTCF binding site in the Igf2/H19 DMD is mutated, the monoallelic expression arising from the imprint is lost [ 11, 12].
RT-PCR followed by pyrosequencing confirmed the Sanger sequencing results and revealed that only residual expression arises from the repressed allele (Additional file 1: Figure S1).
(Later, a single transient stripe of eve2 expression arises in the antennal segment, but the relation of this to early eve2 expression is unclear; Figure 10P-Q, T-U).
More recent theoretical and empirical work suggests that gene duplicates are retained more frequently than the classical model permits and that new function or expression arises through the processes of neo- and subfunctionalization [ 5, 6].
Tissue fractionation experiments show that enhancement of Cnr2 expression arises from the macrophage-enriched stromal vascular fraction of the adipose tissue and the non parenchymal liver cell fraction, whereas Cnr2 expression in adipocytes and hepatocytes remains negligible.
EpoR expression arises at the BFU-E stage, reaches a maximum at the CFU-E and proerythroblast stages and declines thereafter [7], [8].
