(a) The DmPOLγA (tamas)
locus and generation of DmPOLγA knockout (KO) mutant.
Tamas gene encoding DmPOLγA is located on the second
chromosome at cytological position 34D1. The DmPOLγA
knockout founder fly line was generated by ends-out homologous recombination.
Deletion of the tamas gene was confirmed by PCR1, while PCR2
was used as a control. Total DNA was extracted from
DmPOLγA knockout larvae (KO) and wild-type (WT)
flies.
(b) RNA expression levels of tamas and the flanking
genes in the tamas knockout larvae (KO). The expression of
DmPOLγA (tamas) gene was not detected (ND) in the
homozygous (KO/KO, black bar) knockout larvae. The expression of
DmPOLγA (tamas) neighboring genes
was not affected by removal of tamas allele in
DmPOLγA heterozygous (KO/+, grey bar) and homozygous
(KO/KO, black bar) knockout larvae. Total RNA was extracted from 5-day-old
larvae and gene expression was analyzed by qRT-PCR. One-way ANOVA with
Dunnett’s post hoc test. ***p<0.001, **p<0.01,
*p<0.05. Error bars represent S.D. n=5 Data represent two independent
experiments.
(c) Comparison of body size between wild-type (WT, white bar),
heterozygous (KO/+, grey bar) and homozygous DmPOLγA
knockout (KO/KO, black bar) larvae. Homozygous knockout larvae were smaller than
the wild-type and heterozygous knockout larvae. Scale bar=5mm.
(d) Steady-state levels of mtDNA were determined by quantitative PCR in 5-day-old
wild-type (WT, white bar), heterozygous (KO/+, grey bar) and homozygous (KO/KO,
black bar) DmPOLγA knockout larvae. Lack of
DmPOLγA led to severe mtDNA depletion. Data represent at least three
independent experiments. Kruskal-Wallis test with Dunnett’s post hoc
test. ***p<0.001, ** p<0.01, *p<0.05. Error bars represent
S.D. n=4-6.