iRNAblogger

Hi bwschn01. Would you mind giving a little more details about the goal of your experiments? Just a few basic suggestions (that I'm sure you have probably considered) come to mind, but if you gave a little more information about exactly what kind of experiments you would like to run, then I could try to give more specific suggestions.

DISCLAIMER: I am not a microbiologist, but I have done some bacterial genetics; So I'm not sure how helpful I will be.

For phenotyping, you might consider constructing an ectopically regulated strain (for the gene in question). That way you could control exactly when it is expressed without actually mutating the protein coding sequence. You could also try replacing it with homologous genes from related species to see if the phenotype is the same. (I'm not sure which species you are working with, so these might not be possible)

For functional analysis you could try a pulldown to see what interacting proteins come with it. Other than that you might consider running HHPRED on the gene's protein sequence to see if anyone has studied a related protein (bioinformatic approach).

Also, I'd like to add that I heard (I haven't actually read the literature on the matter, I just watched a lecture, so it may or may not be correct) that the liver is better equipped to metabolize fructose, while the rest of our body deals with glucose (comparing just these 2 hexoses: obviously there are more sugars in our bodies than just these two), so the metabolic waste/stress that results from a high-fructose diet is more likely to accumulate in the liver which has negative effects on the body. This observation does not mean that fructose is bad! The most common context (as mentioned by Ringer and iNow) of fructose in a natural diet is in fruits. The presence of fructose in fruits is not necessarily bad because there is lots of fiber which prevents some of the absorption of the fructose, and because of this, fruits do not cause a noticeable amount of metabolic stress on the liver. However, in a diet where the major source of sugar is a high-fructose corn syrup (which is a mixture of 50% fructose 50% glucose), there is typically not that much fiber and consequently absorption is elevated, leading to an increased amount of fructose metabolized in the liver, and a larger amount of metabolic stress to the liver.

Anyhow, this explanation is what I have heard. It would be great to actually see the data. Someone let me know if any of you have heard something similar!

The way that I would rationalize phenomenon (to myself, meaning it is just how I think about/explain it, not how it actually is) would be through the "lens" of control. Non-phosphorylated glucose can easily diffuse out of the cell (I forget if it can actually pass through the membrane, or if it diffuses out of channels...), but phosphorylated glucose does not. This explanation is the rationalization for why glucose transportation is dependent on hexokinase activity: it 1. prevent the glucose from being able to diffuse back out of the cell and 2. preps the glucose for glycolysis and other metabolic processes.

Thinking about your question in this way, it would make more sense to go through glycogen phophorolysis over hydrolysis because then the liver cells can control where the glucose ends up. If there is a need to export the glucose to the blood stream, then that pathway will be favored; if the cells themselves are ATP deficient, then the metabolic pathway will be favored, etc.. With hydrolysis, it might actually be LESS efficient because if the cell decides that it needs more ATP, then it has to wait for the glucose to randomly collide with a hexokinase within the cell and it also runs the risk of losing the glucose (because it may diffuse out of the cell). This explanation is how I would explain this phenomenon to myself (I'm not sure if this explanation was already implied by other answers, but I didn't see mention of it within this thread)