paternal / biparental mitochondria strains... in our species?

[MonDie]

I decided to split this from this thread, where the OP provided this interesting case study.

 

Paternal Inheritance of Mitochondrial DNA (Schwartz and Vissing, 2002)

http://www.nejm.org/doi/pdf/10.1056/NEJMoa020350

 

A biparentally heritable strain of mitochondria might be more fit. What if biparental strains take hold from time to time only to negate themselves after they've succeeded, causing the population to revert to the maternal mode of inheritance? Has this possibility been investigated? I know little about the analysis of the maternal line via mtDNA.

 

My thoughts are this. If such strains are allowed to appear, either they harm the organism too much to succeed—perhaps sperm mtDNA carries more mutation—or the strain quickly negates its own biparentality after succeeding. In the other thread, the OP claimed that parental mitochondria are actively destroyed, but I don't know the mechanism nor whether mitochondria might occasionally bypass this destruction.

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I'm sorry. I get so "creative" when I don't exercise.

[CharonY]

I am not sure what your main hypothesis is, but data so far suggest that heteroplasmy may be deleterious.

[MonDie]

I am not sure what your main hypothesis is, but data so far suggest that heteroplasmy may be deleterious.

 

That was exactly it, a strain of mitochondria that mutates so as to heritable through both parental lines. This entails heteroplasmy.

 

It could be deleterious to the organism yet advantageous to the mitochondria. On second thought, the mitochondrial advantage might not be sizeable enough since the paternal mitochondria are still outnumbered 1000:1 even if they can bypass destruction. So yeah, my idea is pretty really far-fetched!

The idea was that the species might revert to maternal inheritance after the new strain becomes the norm.

Edited March 24, 2015 by MonDie

[CharonY]

The inheritance is mostly not governed by the mitochondrium itself but by its host cells.

[MonDie]

Yes, I could see that. I believe at present the mtDNA isn't known to be responsible for much, and it's miniscule compared to the chromosomes of the nucleus.

 

I found a paper on this destruction of paternal mitochondria.

http://humrep.oxfordjournals.org/content/15/suppl_2/92.full.pdf

Edited March 24, 2015 by MonDie

[CharonY]

There are quite a few papers out there, off the top of my head they had looked into that in fruit flies, hamsters, slime mould and algae. Different pathways, too. I do not think that the link above is actually looking at the mechanisms, though.

Edited March 24, 2015 by CharonY

[MonDie]

There might be little room for discussion if we are in agreement, but I really appreciate your obliging aid!

Edited March 24, 2015 by MonDie

[CharonY]

To be fair, I am not even sure what you want to discuss. I am just providing info on what is generally already known....