High impact information on QCR6

• The function of the QSR1-encoded protein (Qsr1p) and its relationship to the QCR6-encoded protein are unknown [1].
• These results suggest that suppression of the qsr1-1 mutation by QCR6 occurs by a trans-relationship across the outer mitochondrial membrane [1].
• In yeast cell lysates in which QCR6 rescues an otherwise lethal qsr1-1 mutation, Qcr6p is found only in mitochondria, both in respiratory-competent cells and in rho0 cells in which the bc1 complex is no longer present [1].
• QSR1 (quinol-cytochrome c reductase subunit-requiring) is a highly conserved, essential gene in Saccharomyces cerevisiae that was identified through a synthetic lethal screen by its genetic relationship to QCR6, the gene for subunit 6 (Qcr6p) of the mitochondrial cytochrome bc1 complex [1].
• To test whether QCR6, the nuclear gene which encodes subunit 6, might be functionally redundant with any other gene(s), we screened for mutations in yeast genes which are essential when the otherwise non-essential QCR6 is deleted from the yeast chromosome [2].

Biological context of QCR6

• Disruption of the gene for subunit 6 of the yeast cytochrome bc1 complex (QCR6) causes a temperature-sensitive petite phenotype in contrast to deletion of the coding region of QCR6, which shows no growth defect [3].

Other interactions of QCR6

• Suppression of the QCR6 disruption strain by overexpression of QCR9 indicates a critical interaction between these two proteins in the assembly of the cytochrome bc1 complex [3].
• However, deletion of QCR10 synergistically contributes to the temperature-dependent phenotype resulting from deletion of QCR6, the gene for subunit 6 of the cytochrome bc1 complex [4].

References