The mitochondrial histone HM: an evolutionary link between bacterial HU and nuclear HMG1 proteins.
The mitochondrial histone HM is a very abundant protein in yeast mitochondria that wraps DNA and activates transcription in vitro and is required within the cell for proper maintenance of the mitochondrial chromosome. HM and the bacterial histone-like protein HU have similar activities in vitro and can substitute for each other in E coli cells and in yeast mitochondria. HM also appears to be functionally homologous to nuclear HMG1 proteins, with which it shares a high degree of sequence homology. We report here the isolation of extragenic suppressors of the yeast HM mutant temperature-sensitive phenotype. We also examined the effects of the lack of HM protein and of respiration deficiency on yeast cells mutant for the NHP6 proteins, the putative yeast nuclear HMG1 homologues.
Megraw
T L
TL
Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill 27599-7260, USA.
Kao
L R
LR
Chae
C B
CB
D001426:Bacterial Proteins / Q000235:genetics*; D005075:Biological Evolution; D002352:Carrier Proteins / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics*; D024243:HMGB1 Protein; D006609:High Mobility Group Proteins / Q000235:genetics*; D006657:Histones / Q000235:genetics*; D008928:Mitochondria / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics*
D001426:Bacterial Proteins; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D024243:HMGB1 Protein; D006609:High Mobility Group Proteins; D006657:Histones; D009687:Nuclear Proteins; C040330:histone-like protein HU, bacteria