Mitochondria, Plastids and DNA inheritance

[Keith Robison]

cummins at possum.murdoch.edu.au (Jim Cummins) writes:

>" Direct evidence of plastid DNA and mitochondrial DNA in sperm cells
>in relation to biparental inheritance of organelle DNA in Pelargonium
>zonale by fluorescence electron microscopy" A Kuroiwa,et al  Eur J 
>Cell Biol  (1993) 62: 307-313
>According to this paper's abstract both plastids and mitochondria
>contain DNA and may show  biparental inheritance. 

>Two questions
>(1) Is there any other evidence that plastids contain unique DNA?
Yes, though you probably already knew that -- it just most people
aren't familiar with the term plastid -- the generic name
covering chloroplasts, cyanelles, chromoplasts, etc.

>(2) Is there any other evidence of biparental inheritance of
>non-nuclear DNA?  I thought maternal inheritance was obligatory. 

Maternal or paternal inheritance is known for organelles.  Many plants
inherit plastids (that word again! :-) from one parent and mitochondria
from the other, while others inherit both from the same parent.
Biparental inheritance of organelles is a rare phenomenon as
far as I know (in Chlamydomonas, a green alga, rare biparental
organelle inheritance events have been used to recombinationally
map the organelle genomes).


Keith Robison
Harvard University
Department of Cellular and Developmental Biology
Department of Genetics / HHMI

krobison at nucleus.harvard.edu