Mitochondrial chromosome? How does circular dna...

[Gauss44]

Can anyone describe how circular mitochondrial dna gets wrapped around histones to form a chromosome? Or do they do that?

Descriptions, diagrams, and videos are welcome.

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[enervate]

Can you wrap a rubber band around a baseball?

 

[Gauss44]

Can you wrap a rubber band around a baseball?

It works like that?

 

[Czarcasm]

Can anyone describe how circular mitochondrial dna gets wrapped around histones to form a chromosome? Or do they do that?

Descriptions, diagrams, and videos are welcome.

Mitochondrial DNA is still an area of research. According to the endosymbiotic theory, the mitochondria is the result of years of evolution initiated by endocytosis of bacteria and blue-green algae. What we do know is that DNA in bacteria lacks the intricate organization found inside the Eukaryotic nucleus. They lack a nucleus, so if I recall correctly, the DNA just floats about inside the cytsol, so it's likely mtDNA is organized in similar way.

 

[gettheleadout]

Can anyone describe how circular mitochondrial dna gets wrapped around histones to form a chromosome? Or do they do that?

Descriptions, diagrams, and videos are welcome.

"Chromosome" is an odd choice of word to describe the structure of non-linear DNA. Mitochondria have a singular mtDNA chromosome, but it isn't packaged into chromatin. mtDNA doesn't form chromatin, and you can't assume its arrangement actually involves histones either. As Czar said above, it's likely derivative of prokaryotic DNA, which is also circular, lacks histones, and arranges into a structure different eukaryotic chromatin. How is mtDNA packaged? I have no idea. I would guess closer to the prokaryotic genophore structure than eukaryotic chromatin, but this is quite a specific detail. I really wouldn't worry about it.

 

[Jepstein30]

"Chromosome" is an odd choice of word to describe the structure of non-linear DNA. Mitochondria have a singular mtDNA chromosome, but it isn't packaged into chromatin. mtDNA doesn't form chromatin, and you can't assume its arrangement actually involves histones either. As Czar said above, it's likely derivative of prokaryotic DNA, which is also circular, lacks histones, and arranges into a structure different eukaryotic chromatin. How is mtDNA packaged? I have no idea. I would guess closer to the prokaryotic genophore structure than eukaryotic chromatin, but this is quite a specific detail. I really wouldn't worry about it.

prokaryotes are wrapped around histone-like proteins though.. so could be very similar for mtDNA

 

[gettheleadout]

prokaryotes are wrapped around histone-like proteins though.. so could be very similar for mtDNA

Right, all I said was they're not histones. Yes, the genophore incorporates proteins, but I don't see why it's important worry about for mitochondria.

 

[Jepstein30]

Right, all I said was they're not histones. Yes, the genophore incorporates proteins, but I don't see why it's important worry about for mitochondria.

Meant it's likely packaged in a very similar way to eukaryotes so the OPs question is still quite relevant. You're right though, wouldn't really worry about this. If asked obscurely, it'll be in the passage somewhere.

 

[Czarcasm]

I use to know this stuff so well. Makes me sad I forgot so much. Biology has always been my favorite subject.

 

[gettheleadout]

Meant it's likely packaged in a very similar way to eukaryotes so the OPs question is still quite relevant. You're right though, wouldn't really worry about this. If asked obscurely, it'll be in the passage somewhere.

"Likely" is a stretch without any reason to believe so.

 

[Jepstein30]

"Likely" is a stretch without any reason to believe so.

histone-like proteins 😉

if you're interested, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC373113/pdf/microrev00050-0009.pdf

talks about how its all packaged.

Seems like it is packaged into chromatin and are wrapped around the histone-like proteins but that was a cursory read..

this is a test based on analytical skills.. if you're asked about something, you're allowed (and supposed to) draw parallels using information you are given or are supposed to know..