Functional enrichment analyses on the parental genes of DECs
Both circRNAs and mRNAs are derived from shared pre-mRNA precursors, so
we next explored the functional roles of the parental genes sequences
from which these DECs were derived using the ClusterProfiler tool to
conduct GO and KEGG enrichment analyses for the 127 DECs (four
intergenic circRNAs had been excluded from this analysis).
The top 30 GO terms enriched by these DECs were compiled in Figure 3A.
Significant biological process terms included B cell homeostasis
(GO:0001782), lymphocyte homeostasis (GO:0002260), leukocyte homeostasis
(GO:0001776), RNA phosphodiester bond hydrolysis, endonucleolytic
(GO:0090502), homeostasis of number of cells (GO:0048872), small GTPase
mediated signal transduction (GO:0007264), positive regulation of GTPase
activity (GO:0043547), antigen receptor-mediated signaling pathway
(GO:0050851), sister chromatid cohesion (GO:0007062), B cell receptor
signaling pathway (GO:0050853), covalent chromatin modification
(GO:0016569), regulation of small GTPase mediated signal transduction
(GO:0051056), regulation of GTPase activity (GO:0043087), RNA
phosphodiester bond hydrolysis (GO:0090501), chromosome organization
(GO:0051276), chromosome segregation (GO:0007059), nucleocytoplasmic
transport (GO:0006913), nuclear transport (GO:0051169), chromatin
organization (GO:0006325), and protein polymerization (GO:0051258). Top
enriched cellular component terms included Golgi-associated vesicle
membrane (GO:0030660), Golgi-associated vesicle (GO:0005798), nuclear
speck (GO:0016607), nuclear body (GO:0016604), lytic vacuole
(GO:0000323), lysosome (GO:0005764), cytosol (GO:0005829), chromatin
(GO:0000785), vacuole (GO:0005773), lysosomal membrane (GO:0005765),
spindle (GO:0005819), intracellular membrane-bounded organelle
(GO:0043231), nucleoplasm (GO:0005654), vacuolar membrane (GO:0005774),
cytoplasm (GO:0005737), intracellular ribonucleoprotein complex
(GO:0030529), ribonucleoprotein complex (GO:1990904), intracellular
organelle (GO:0043229), and cytoplasmic region (GO:0099568). Moreover,
top molecular function terms included GTPase activator activity
(GO:0005096), endoribonuclease activity (GO:0004521), GTPase regulator
activity (GO:0030695), organic cyclic compound binding (GO:0097159),
ribonuclease activity (GO:0004540), RNA binding (GO:0003723), enzyme
activator activity (GO:0008047), ubiquitin-protein transferase activity
(GO:0004842), ubiquitin-like protein transferase activity (GO:0019787),
endonuclease activity (GO:0004519), Ras GTPase binding (GO:0017016), Rab
GTPase binding (GO:0017137), nucleic acid binding (GO:0003676), small
GTPase binding (GO:0031267), enzyme regulator activity (GO:0030234),
kinase binding (GO:0019900), molecular function regulator (GO:0098772),
GTPase binding (GO:0051020), protein serine/threonine kinase activity
(GO:0004674), protein kinase activity (GO:0004672), tubulin binding
(GO:0015631), purine ribonucleoside triphosphate binding (GO:0035639),
cytoskeletal protein binding (GO:0008092), nuclease activity
(GO:0004518), and transferase activity (GO:0016740).
KEGG enrichment analysis was conducted and led to the identification of
143 pathway terms, 44 of which were found to be significantly enriched
by these DEC parental genes (P <0.05). The top 30
enriched pathways were compiled in Fig. 3B, mainly including the ErbB
signaling (hsa04012), Phospholipase D signaling (hsa04072), Gap junction
(hsa04540), GnRH signaling (hsa04912), Choline metabolism in cancer
(hsa05231), Endocrine and other factor-regulated calcium reabsorption
(hsa04961), T cell receptor signaling (hsa04660), B cell receptor
signaling (hsa04662), Thyroid hormone synthesis (hsa04918), Gastric acid
secretion (hsa04971), Bacterial invasion of epithelial cells (hsa05100),
Chronic myeloid leukemia (hsa05220), mTOR signaling (hsa04150), Ras
signaling (hsa04014), EGFR tyrosine kinase inhibitor resistance
(hsa01521), and Oxytocin signaling (hsa04921) pathways.