The unsaturation degree of the FA increases during the colder seasons, as mussels require these FA to maintain membrane fluidity (Hall et al. 2002).
Ergosterol is an important target because it maintains membrane fluidity, asymmetry and integrity and therefore various cell functions (Rodriguez et al. 1985).
Microalgae from northern high latitudes, exposed to cold temperatures, may be especially promising candidates as previous studies have shown increasing unsaturation of FA in response to decreasing growth temperatures in different microalgae, most likely to maintain membrane fluidity and function.
Recent work in fluxomics reveals the mechanism of how membrane damage negatively affects energy metabolism while lipidomic and transcriptomic analyses show that strains evolved to be tolerant maintain membrane fluidity under stress through a variety of mechanisms such as incorporation of cyclopropanated fatty acids, trans-unsaturated fatty acids, and upregulation of cell wall biosynthesis genes.
PUFAs are important constituents of phospholipids in cell membranes, assuring the correct environment for membrane protein function, maintaining membrane fluidity, and moreover PUFAs have been described to play a role in regulating gene transcription [53].
In addition, homeoviscous adaptations, i.e. increased polyunsaturation of membrane phospholipids that maintain membrane fluidity in the brain during prolonged exposure to cold temperature [6], [7] enhance the susceptibility to oxidative stress [8].
They maintain membrane fluidity and permeability, and modulate activity of membrane-bound proteins and ion channels.
Melatonin helps maintain membrane fluidity by preventing LPO and scavenging ROS and RNS [ 169].
In plants, their concentrations increase to maintain membrane fluidity as an adaptation to increasing light intensity [ 20].
Cholesterol is an integral component of lipid membranes in eukaryotic cells that is required for maintaining membrane fluidity and facilitating the trafficking and signaling of membrane-associated proteins.
