rakuenso Posted November 6, 2004 Posted November 6, 2004 This may sound like a strange question, but due to my lack of cellular biology I can't seem to determine the feasibility of such a question: Is it possible to inject chloroplasts into an animal cell and force symbiosis, and thus allowing it photosynthesize and respirate without forming cell walls and the big ass vacuoles that plants have? I also realized that the replication of the organelles require additional genetic information to be injected into various chromosomes, so any thoughts?
gene Posted November 6, 2004 Posted November 6, 2004 Might there be some tissue rejection? And the immune system would probably destroy it.
rakuenso Posted November 6, 2004 Author Posted November 6, 2004 I understand that, but for eukaryotes to evolve in the first place, there must have been someway to coax it into accepting it. However, i'm talking about singular cells, ex situ of the human body grown independently of the immune system.
gene Posted November 10, 2004 Posted November 10, 2004 maybe there some radiation that can "weaken" or "deactivate" the immune system. to slow down the tissue rejection. Afterall, it is not at all good to be injecting chloroplast into animal cells. Ethnics. Just like stems cells. God created us they way we are, we are not meant to photosynthesise, i guess.
Xavier Posted November 12, 2004 Posted November 12, 2004 Getting a chloroplast into a cell might be feasible - there is a lot of research into micelles and the like which can deliver payloads of drugs to specific sites within cells. (For example look over Advanced Drug Delivery Reviews 55(6) http://www.sciencedirect.com/science/journal/0169409X) These could probably be adapted to something as large as a chloroplast. It might even be possible to place the chloroplast in its own vesicle, away from the multitudinous enzymes and messengers, with ion transport channels to shuttle the oxygen, CO2, glucose etc. between the vesicle and the cytoplasm. It might even be possible to set this up in a way that it doesn't trigger immediate apoptosis ('cell suicide'), though this would have to be by trial and error as apoptosis is not really understood at all. But even then nothing would happen unless you altered the internal workings of the cell in very fundamental ways to make all the necessary carrier and messenger proteins travel to and from the chloroplast. This is the most complex part (no hope for trial and error) and the least understood. To genetically engineer this correctly would be more difficult that adapting an algal cell to work symbiotically within a human. There are examples of this sort of symbiosis, for example lichen and coral where plant and non-plant cells live so closely together that we think of them as essentially a single multicellular creature.
gene Posted November 12, 2004 Posted November 12, 2004 wouldn't the green pigment in the cholorplast make us look Green?
gene Posted November 13, 2004 Posted November 13, 2004 Seriously, in plants, they look green due to the chlorophyll in choloroplast. So, by injecting it into our cell ( as seen quite possible in Xavier's post) would that cause our cell to turn green? So, tell me is that rubbish?
premjan Posted November 13, 2004 Posted November 13, 2004 I suppose if there was no other pigment it would look green, bu I do not know for sure. I thought you were a malicious poster. Never mind.
rakuenso Posted November 13, 2004 Author Posted November 13, 2004 Also on another note, why arent there any cells which have cholorplast but not mitochondria?
premjan Posted November 13, 2004 Posted November 13, 2004 Also on another note, why arent there any cells which have cholorplast but not mitochondria? I'm pretty sure that mitochondria are needed to produce energy-rich molecules (ATP) for the cell to live (most cells). There are probably simple cells which lack mitochondria because they have some other way of arranging an energy supply but I can't remember offhand which ones.
rakuenso Posted November 13, 2004 Author Posted November 13, 2004 I'm pretty sure that mitochondria are needed to produce energy-rich molecules (ATP) for the cell to live (most cells). There are probably simple cells which lack mitochondria because they have some other way of arranging an energy supply but I can't remember offhand which ones. A lot of prokaryotic cells recieve their energy from mesosomes, as to how? don't ask me.
Skye Posted November 13, 2004 Posted November 13, 2004 A problem with injecting chloroplasts into an animal cell might be that so many of the genes necessary for the functioning of chloroplasts are in the plants genome.
rakuenso Posted November 13, 2004 Author Posted November 13, 2004 i wish for the day when a photosynthetic human becomes a reality =D
Proton Head Posted November 14, 2004 Posted November 14, 2004 Even though green humans are a funny idea, the change in skin colour would be the only good thing those chloroplasts would do you. Think about it. Plants don't move, plants don't think, and even though they do neither of these actions (which use tremendous amounts of energy), their surface area to volume is immensely larger than that of animals. There just wouldn't be a way an animal could satisfy a substantial amount of its energy need through photosynthesis (even optimized one), given their current surface area. It could work if you were a Bulbasaur with a bush growing from your back. As to how to transfer the choloplasts, such transfers are already possible though microinjection for example. Now to make them work in the animal cells, you would either have to genetically modify the chloroplast genome or the animal genome, to return the genes the chloroplast genome has lost over evolution, now residing in the plant genome. If you chose to incorporate these genes into the animal genome you would probably have to incorporate a deal of other genetic material used in the modification and transport of these chloroplast enzymes. Apoptosis and immunological reactions might be a problem though this could possibly be overcome by modifying the outer membrane of the chloroplast, and changing the sugar content of its proteins.
gene Posted November 14, 2004 Posted November 14, 2004 i think it would disgusting to have green human. So, is there any way we can "remove" the green pigment without compromising the ability of the chloroplast to carry out photosynthesis?
Proton Head Posted November 14, 2004 Posted November 14, 2004 Even now there exists a variety of different photosynthetic pigments in the natural world, but I don't know one that would fit nicely into human skin. Besides I believe the human melanine (substance in the skin which protects us against high energy radiation) is going to prevent efficient photosynthesis. On the other hand perhaps it would be able to convert melanine or a related compound into functioning as a photosynthetic pigment, though such actions would take much more effort than simple chloroplast injection. Either way the efforts would be in vain, as you couldn't satisfy your energy need with photosynthesis in your current form.
gene Posted November 14, 2004 Posted November 14, 2004 Yes. the energy produced would be insufficient.
chadn Posted November 14, 2004 Posted November 14, 2004 Besides I believe the human melanine (substance in the skin which protects us against high energy radiation) is going to prevent efficient photosynthesis. Doubtful, considering that photosynthetic pigments mostly absorb visible light, especially light in the red portion of the spectrum. Unless Im mistaken, melanine doesnt do much against visible light. Either way the efforts would be in vain, as you couldn't satisfy your energy need with photosynthesis in your current form. But you could lower the amount of food you needed because a portion would be satisfied by photosynthesis, as long as you spent sufficient time exposed to light in some form. Of course theres the problem of clothing. If our bodies photosynthesized it would be to our advantage to all become nudists. Of course the biggest obstacle that I see is an adequate source of CO2. We would either need to obtain it from cellular respiration or genetically engineer stomata into our skin.
gene Posted November 14, 2004 Posted November 14, 2004 another note. how would the oxygen be transported? if we assume there are no genetically engineered stomata in our skin. what if these stomata allows bacteria and germs to more easily enter our body? there seems to be complications.
Radical Edward Posted November 14, 2004 Posted November 14, 2004 Also on another note, why arent there any cells which have cholorplast but not mitochondria? because chloroplasts became intercellular symbionts after mitochondria, so then you have two lineages. one lineage with chloroplasts and mitochondria, and one lineage with mitochondria only. For there to be organisms with chloroplasts and no mitochondria would require a separate formation of a symbiotic partnership between cells containing no mitochondria and chloroplasts. THe only other alternatice is if chloroplasts came first, then mitochondria, but then all cells would have chloroplasts.
Radical Edward Posted November 14, 2004 Posted November 14, 2004 This may sound like a strange question' date=' but due to my lack of cellular biology I can't seem to determine the feasibility of such a question: Is it possible to inject chloroplasts into an animal cell and force symbiosis, and thus allowing it photosynthesize and respirate without forming cell walls and the big ass vacuoles that plants have? I also realized that the replication of the organelles require additional genetic information to be injected into various chromosomes, so any thoughts?[/quote'] I would suggest injecting them into a gamete, embryonic formation results in the new organism recognising all present cells as self. which is why embryos can form chimera. The problem is, like in the case of mitochondria, many of the genes required to produce chloroplasts are in the nucleus of the organism and so injecting mitochondria alone would be useless since they would just die. Injeting into an adult animal would probably result in an immune reaction, unless you managed to inject it directly into the cells, and there were no surface proteins identifying that the chloroplast was there. That would be hard though.
Radical Edward Posted November 14, 2004 Posted November 14, 2004 another note. how would the oxygen be transported? if we assume there are no genetically engineered stomata in our skin. assuming it is possible to get chloroplasts into the cells, the oxygen would be transported in the blood, just as it, and all other dissolved gases, are now. There would be no need for stomata.
chadn Posted November 14, 2004 Posted November 14, 2004 assuming it is possible to get chloroplasts into the cells, the oxygen would be transported in the blood, just as it, and all other dissolved gases, are now. There would be no need for stomata. Stomata would be needed, or some other equivalent to them.The CO2 produced from respiration is not in a form used in photosynthesis and the bloood works to get rid of CO2, not supply it. So you still have the problem of a carbon supply.
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now