Mitochondrial Transfer by Photothermal Nanoblade Restores Metabolite Profile in Mammalian Cells.

Journal: 
Cell Metab
Publication Year: 
2016
Authors: 
Ting-Hsiang Wu
Enrico Sagullo
Dana Case
Xin Zheng
Yanjing Li
Jason S Hong
Tara TeSlaa
Alexander N Patananan
J Michael McCaffery
Kayvan Niazi
Daniel Braas
Carla M Koehler
Thomas G Graeber
Pei-Yu Chiou
Michael A Teitell
PubMed link: 
27166949
Public Summary: 
Mitochondrial DNA (mtDNA) sequence alterations are challenging to generate but desirable for basic studies and potential correction of mtDNA diseases. Here, we report a new method for transferring isolated mitochondria into somatic mammalian cells using a photothermal nanoblade, which bypasses endocytosis and cell fusion. The nanoblade rescued the pyrimidine auxotroph phenotype and respiration of rho0 cells that lack mtDNA. Three stable isogenic nanoblade-rescued clones grown in uridine-free medium showed distinct bioenergetics profiles. Rescue lines 1 and 3 reestablished nucleus-encoded anapleurotic and catapleurotic enzyme gene expression patterns and had metabolite profiles similar to the parent cells from which the rho0 recipient cells were derived. By contrast, rescue line 2 retained a rho0 cell metabolic phenotype despite growth in uridine-free selection. The known influence of metabolite levels on cellular processes, including epigenome modifications and gene expression, suggests metabolite profiling can help assess the quality and function of mtDNA-modified cells. Thus, this apparatus allows the transfer of mitochondria from a host cell to a recipient cell, bypassing the typical and tedious approach of cell fusion assays.
Scientific Abstract: 
mtDNA sequence alterations are challenging to generate but desirable for basic studies and potential correction of mtDNA diseases. Here, we report a new method for transferring isolated mitochondria into somatic mammalian cells using a photothermal nanoblade, which bypasses endocytosis and cell fusion. The nanoblade rescued the pyrimidine auxotroph phenotype and respiration of rho0 cells that lack mtDNA. Three stable isogenic nanoblade-rescued clones grown in uridine-free medium showed distinct bioenergetics profiles. Rescue lines 1 and 3 reestablished nucleus-encoded anapleurotic and catapleurotic enzyme gene expression patterns and had metabolite profiles similar to the parent cells from which the rho0 recipient cells were derived. By contrast, rescue line 2 retained a rho0 cell metabolic phenotype despite growth in uridine-free selection. The known influence of metabolite levels on cellular processes, including epigenome modifications and gene expression, suggests metabolite profiling can help assess the quality and function of mtDNA-modified cells.