PIN1 may act directly via phosphorylated serine/threonine proline motifs in calpastatin, or indirectly via other PIN1 substrates that control calpastatin.
Compounds capable of initiating tumour development may act directly to cause genetic damage, or they may require metabolic conversion by an organism to become reactive.
As a result, these plants showed an increased accumulation of a mixture of flavonoids and anthocyanins, with a concomitant decrease in proanthocyanidins, suggesting that ANS may act directly on different flavonoid substrates of DOX reactions.
Drugs may act directly on the smooth muscle cells, or they may act indirectly for example, by altering the activity of nerves of the autonomic nervous system that regulate vasoconstriction or vasodilation.
GH may act directly on tissues, but much of its effect is mediated by stimulation of the liver and other tissues to produce and release insulin-like growth factors, primarily insulin-like growth factor 1 (IGF-1; formerly called somatomedin).
Pro-inflammatory cytokines may act directly on nociceptor terminals to induce pain [39].
Once in the cell, the viral genome is transcribed (although some viral RNA genomes may act directly as mRNAs) and translated by the cell using the cellular machinery and energetic resources.
Specifically, MMP-2 may act directly by degrading ECM components like type III collagen or indirectly by activating pro-MMP-2 or by inducing tumor angiogenesis through vascular endothelial growth factors (Tetu et al. 2006).
Taken together, our studies demonstrate that, in the absence of serum, alpha-defensin-1 may act directly on the virus, but, in the presence of serum, its effects are on the cell, where it inhibits HIV-1 replication.
The drug aims to shut down this process by gumming up an endothelin receptor found on bone cells; it also may act directly on prostate cancer cells to inhibit their growth.
Furthermore, the generated hydroxyl radicals may act directly on cellulose polymers [25].
