An alternative reason could be that head patterning lags behind GZ patterning as indicated by the later expression of Tc-wg compared with the GZ (Fig. 7; supplementary material Fig. S1).
Regulation of developmental genes was prominent on both Days 1 and 7, but those involved in neuronal differentiation were only overrepresented on Day 7. The genes within the category 'regulation of neurotransmitter levels' were interesting because they tended to be down-regulated during the first 24 h of the experiment, followed by a later increase in expression.
We observed that syndecan-4 mRNA and protein expression were regulated in a temporally and spatially specific manner, such that initial expression of syndecan-4 was localized to adventitial cells followed by later expression in the neointima.
This was corroborated by a later report whereby lack of Spry2 expression along with high level of ERK activation was evident in putative tumorigenic cells of KRASG12D-induced neoplasia in mouse lungs [ 156].
A specific prediction of our detailed cis-regulatory analysis of the Strongylocentrotus purpuratus (Sp) endo16 gene was that the later expression of this gene would be driven by a midgut-specific transcriptional regulator.
The extended fiber development period, as indicated by higher expression at a later DPA, may help explain why G. barbadense has an extra long staple cotton.
C/EBPβ then induces expression of PPARγ and C/EBPα, which form a positive feedback loop by activating each other's expression and play roles at a later stage by inducing and maintaining the expression of adipocyte-specific genes (Rosen and MacDougald 2006; Tontonoz and Spiegelman 2008).
This increase in expression was first detectable on perivascular cells, followed by a clear expression on parenchymal cells, including microglia, at later time points (Fig. 3).
In addition, all HIV-infected subjects in our study were asymptomatic and therefore the expression of CXCR4 might be affected by HIV at a later stage.
This early peak is followed by a second, later phase of increased cytokine expression [ 9, 10].
