Fig. 4

The snoRNA abundance classes correlate differently with their HG abundance due to different HG characteristics. A SnoRNAs display a wide range of correlation with their HG abundance. The scatter plot indicates the correlation of abundance of the snoRNA/HG pairs and their associated false discovery rate (FDR)-adjusted p value for each snoRNA. The green and gray dots indicate respectively significant (p < 0.05) and non-statistically significant correlations. B The abundance of most TE snoRNAs positively correlates with that of their HG as opposed to UE snoRNAs. The number of snoRNAs displaying various degrees of correlation depending on the abundance class is represented as a bar graph. C Non-coding HGs are more positively correlated with their embedded snoRNAs than protein-coding HGs. Shown are the density distributions for either UE or TE snoRNAs as a function of the correlation of abundance between the snoRNA and either their protein-coding or non-coding HG. The stars represent the statistical significance of the difference between the two distributions (Mann-Whitney U test, ***p < 4 × 10^− 15 and ***p < 1 × 10^− 5, respectively for UE and TE snoRNAs). D Most anticorrelated non-coding HGs are subject to NMD. The proportion of protein-coding and non-coding HGs subject to NMD is plotted as a function of the correlation of abundance with their embedded snoRNAs (< − 0.25: anticorrelation [− 0.25; 0.25]: non-correlation and > 0.25: positive correlation), for each snoRNA abundance class. E Correlation between UE snoRNAs and their HG abundance is determined at least in part by the HG function. The proportion of anticorrelated and positively correlated snoRNAs embedded in each functional HG group is shown as a stacked bar chart, for each snoRNA abundance class. The number above each bar represents the number of HGs in that subgroup. The stars indicate the statistical significance of the difference between anticorrelated and correlated groups of HGs (Fisher’s exact test, *p < 0.05 and ***p < 2 × 10^− 4)