Mitochondria play a key role in essential cellular functions. A deeper understanding of mitochondrial molecular processes is hampered by the difficulty of incorporating foreign nucleic acids into organelles. Mitochondria of most eukaryotic species import cytosolic tRNAs. Based on this natural process, we describe here a powerful shuttle system to internalize several types of RNAs into isolated ...

The effect of the inclusion of EDTA and of heparin, in media used in the isolation of mitochondria, on the mitochindrial ribosome has been investigated. 1. Mitochondria isolated from Neurospora crassa in the presence of EDTA contain only a single type of monomeric ribosome, viz. 73 S. 2. Mitochondria isolated in the presence of Mg 2÷ contain both 79-S and 73-S monomeric ribosomes. The heterogen...

Connexin 43 (Cx43), which is highly expressed in the heart and especially in cardiomyocytes, interferes with the expression of nitric oxide synthase (NOS) isoforms. Conversely, Cx43 gene expression is down-regulated by nitric oxide derived from the inducible NOS. Thus, a complex interplay between Cx43 and NOS expression appears to exist. As cardiac mitochondria are supposed to contain a NOS, we...

Mitochondria isolated from normal mammary glands taken from lactating and nonlactating C3H mice were compared with those isolated from mammary adenocarcinomas. Functional mitochondria could be obtained from the normal mammary glands only when milk was not present in the tissue prior to homogenization and when bovine serum albumin was added to the isolation medium. Albumin also protected tumor m...

We have developed a new method for introducing large numbers of isolated mitochondria into tissue culture cells. Direct microinjection of mitochondria into typical mammalian cells has been found to be impractical due to the large size of mitochondria relative to microinjection needles. To circumvent this problem, we inject isolated mitochondria through appropriately sized microinjection needles...