Abstract
CD8 subunit alpha (CD8A) is an important gene in immunity and is involved in the functional regulation of T lymphocytes. Previous studies have confirmed that interfering with CD8A expression inhibits the proliferation and induces the apoptosis of T lymphocytes. However, the specific regulatory mechanism of CD8A in chicken T lymphocytes remains unreported. In this study, whole-transcriptome RNA sequencing analyses of chicken T lymphocytes with interference of CD8A were performed. The whole-transcriptome RNA sequencing results revealed 465 differentially expressed genes (DEGs), 108 differentially expressed miRNAs (DEMs), 679 differentially expressed lncRNAs (DELs), and 18 differentially expressed circRNAs (DECs). The competitive endogenous RNA (ceRNA) regulatory network analysis indicated that interference with CD8A may regulate "interleukin-8 receptor binding", "positive regulation of the cellular defense response", "glycosaminoglycan biosynthesis-keratan sulfate", "glycosphingolipid biosynthesis-ganglio series", etc., thereby regulating the development of chicken T lymphocytes and immunity. Moreover, we extracted eight genes that were significantly enriched in the GO and KEGG analyses, including MITF, ARID5B, IL8L2, RUNX1, JAK1, MKNK2, TIPARP, and ST3GAL1, which are considered to be immune genes that are regulated by miR-1306-5p, miR-24-3p_R+1, miR-2478_L-1_1ss2TG, miR-106a-5p, and miR-17-5p. These miRNAs are competitively combined with other lncRNAs, including MSTRG.3287.1, MSTRG.851.3, MSTRG.5709.2, MSTRG.8606.10, MSTRG.8606.9, MSTRG.6504.2, and MSTRG.2145.4, etc., via circRNAs, including cirRNA145 and cirRNA147. Therefore, CD8A may affect T-cell development and thereby influence the immunity of chickens through these ceRNA regulatory networks and signaling pathways.