Recent studies indicate that a number of the different K2P2.1 (TREK-1) modulatory inputs sensed on either side of the membrane converge on an extracellular C-type gate (Bagriantsev et al, 2011) that involves the selectivity filter.
This coupling further supports the idea that diverse inputs sensed by different parts of the channel converge on a single gate (Bagriantsev et al, 2011) and suggests that the polymodal gating mechanism of K2P2.1 (TREK-1) has evolved through coupling of various molecular sensors to a common gating apparatus.
The daylight photoperiodic input, sensed mainly by intrinsically blue-light-sensitive retinal ganglion cells, is transmitted by their axons to a ventrolateral and largely rostral "core" region of each SCN, where a key neurotransmitter is vasoactive intestinal polypeptide (VIP).
Engineered biological systems that integrate multi-input sensing, sophisticated information processing, and precisely regulated actuation in living cells could be useful in a variety of applications.
Furthermore, early antigen discrimination is all-or-none (Das et al., 2009), with limited dynamic ranges in both antigen input sensing and response output (Altan-Bonnet and Germain, 2005; Tkach and Altan-Bonnet, 2012; Huang et al., 2013), but long-term signaling can widen the gradation of functional responses.
Building on this work, we adapted an input or sensing system based on bacterial chemotactic binding proteins and HKs, resulting in a complete eukaryotic signal transduction system.
The TOR complexes are regulated by nutrients, stress, or ribosomes, but the mechanisms by which these inputs are sensed and how this information is transduced, with the notable exceptions discussed above, to ultimately regulate kinase activity remain largely unknown.
Neurons residing in these areas exhibit rapid regulation in response to food intake, suggesting the involvement of inputs from systems sensing nutrient consumption (Johnstone et al. 2006; Singru et al. 2007).
Only a few predictions of the input signals sensed by these systems could be made confidently, and most of these cases involved responses to the binding of small effectors.
In all these cases, small gene circuits compute their output based on the external/internal input signal sensed.
Intuitively, the two parts of input policy, namely, sensing probability and sub-channel symbol distribution (in (mathcal {X})), can be optimized independently.
