https://www.reddit.com/r/askscience/comments/1h1nlzv/if_invertebrates_dont_have_insulin_then_how_do/
created by PartNo8984 on 28/11/2024 at 04:16 UTC
257 upvotes, 4 top-level comments (showing 4)
So maybe I'm misguided in this but I've recently been learning about the insulin pathway and it causing GLUT4 to be takes into certain tissues to intake glucose. They mention in some videos that vertebrae's have developed this implying that at least some invertebrates do not have this insulin pathway?
So how do these creatures get energy into the cell?
My first thought would be that photosynthesis does not need insulin to make glucose useful to plants so there have to be some evolutionary processes that can facilitate this.
Comment by HermitAndHound at 28/11/2024 at 17:23 UTC
155 upvotes, 2 direct replies
Glucose pathways in insects I leave to others, but insects do produce insulin. They just use it differently. It regulates diapause in some and acts as a pheromone in others.
Shows how hormones are really just soluble signals, what exactly they trigger can vary wildly.
Comment by CorvidAlles at 28/11/2024 at 19:34 UTC
44 upvotes, 1 direct replies
As an example, I recently tried expired human insulin on a insect tissue sample. It apparently worked to inhibit sugar mobilization from glycogen. We didn't check increase in glucose storage though. It did seem to oppose adipokinetic hormone action (insect glucagon). Really neat how conserved it is. We're working on a dose response right now.
Check out Oliveira's work from Utah, their lab found weaponized insulin from cone snails that targets fish to induce hypoglycemia.
Comment by PredawnDecisions at 28/11/2024 at 21:52 UTC
16 upvotes, 0 direct replies
GLUT4 is one type of glucose transporter, there are many others, and not all of them are insulin responsive. GLUT1, 2, and 3, for example, do not require insulin.
Additionally, as others have noted, these transport proteins are highly conserved within mammals, but the applicability of the labels decrease as you go beyond vertebrates. Many of the scenarios associated with human hyperglycemia simply don’t apply in species without complex nervous systems, and so they don’t require the complicated regulatory systems found in vertebrates.
Comment by marryjw at 29/11/2024 at 06:12 UTC
5 upvotes, 0 direct replies
I think it is common for invertebrates to use other hormones or signaling pathways to regulate their glucose uptake instead of insulin. Else there might be different glucose transporters that are constitutively active or that are activated by other factors. Different organisms handle glucose metabolism differently, and for me there is still a lot to learn about this topic.