Anhydrbiossis

Question 1

How does threhalose work

Answer 1

Trehalose has been proposed to act as a molecular stabilizer replacing water and to further stabilize cellular structure through the formation of amorphous glasses, a
process known as vitrification
(Trehalose
and other organic osmolytes also exert thermodynamic pressure to maintain proteins in their native conformation under hydrated
conditions (25) and, recently, trehalose has been shown to stimulate autophagy. Therefore, under stress conditions such as those imposed by water loss, trehalose could have a role in both prevention of protein denaturation and aggregation

Not seen to be essential

Question 2

heat-shock proteins

Answer 2

Cryptobiosis has been suggested to rely on the synthesis of molecular chaperones such as heat-shock-proteins, which may assist folding of newly synthesized proteins, control their final intracellular location, as well as protect them from stress-associated denaturation and aid in renaturation
Actually seen to be involved in the repair processes after
desiccation rather than acting as a biochemical stabilizer

the upregulation of a protein with a molecular weight during cryptobiosis - an isoform hsc70

Question 3

Trehalose points

Answer 3

trehalose may substitute for water in the hydrogen bonded
hydration shell of proteins- prevents aggregation, so that
degradative cannot occur.

the accumulation of trehalose during stress may not always be advantageous. While high quantities of trehalose may offer better protection to drying cells, they may also be incompatible with chaperone-assisted protein re-folding during recovery from the dry state, thus exposing the
cells to damage upon rehydration.

Question 4

Overview of protection of drying out 3 points

Answer 4

limit cellular
damage to a reparable level upon drying, 2) maintain structural
and physiological integrity of cells in the dried state, and
3) repair cell damage rapidly and efficiently upon rehydration.