All statistical analyses were performed using the statistical software GraphPad Prism 7. All data are presented as mean ± standard error (s.e.m.). Shapiro-Wilk tests and F tests were used to test the normality and equal variance assumptions, respectively. Two-tailed t-tests were used to assess differences between two experimental groups with equal variance. For multiple groups, two-way or two-way repeated-measures ANOVAs followed by Turkey tests were used. Statistical significance was set as p < 0.05. Grubbs outlier test was performed and samples that varied > 2 standard deviations from the mean were removed.
