Molecular analysis of a ras-like nuclear (Ran) gene from Penaeus monodon and its expression at the different ovarian stages of development

Analysis of the resistance of small peptides from Periplaneta americana to hydrogen peroxide-induced apoptosis in human ovarian granular cells based on RNA-seq

Apoptosis of ovarian granular cells is closely related with weakening fertility of women. Hence, resisting apoptosis of human ovarian granular cells is of important significance. According to previous studies, DAPI fluorescence staining experiment and Western Blot test of Caspase-3 demonstrate that small peptides from Periplaneta americana (SPPA) can improve hydrogen peroxide (H₂O₂) -induced apoptosis of human ovarian granular cells (KGN cells). However, the molecular mechanism of SPPA resistance against apoptosis of granular cells still remains unknown. In this study, key genes and signaling pathways for SPPA to resist H₂O₂-induced apoptosis of KGN cells were determined through transcriptome sequencing (RNA-seq). Experiments were divided into three groups, namely, the control group, H₂O₂ group and H₂O₂ + SPPA group. A total of 1196 differentially expressed genes (DEGs) were screened by comparing the control group and the H₂O₂ group, and 2805 DEGs were screened by comparing the H₂O₂ group and H₂O₂ + SPPA group. It is important to note that 87 overlapping genes were identified upregulating in H₂O₂ exposure, but downregulating in SPPA repair. Another 151 overlapping genes were identified downregulating in H₂O₂ exposure, but upregulating in SPPA repair. These 238 overlapping genes have significant enrichment in multiple KEGG pathways. Among them, 13 genes play significant roles in SPPA resistance process of cell apoptosis: EIF3D, RAN, UPF1 and EIF2B4 participate in RNA transport; ACTG1, SIPA1 and CTNND1 participate in Leukocyte transendothelial migration; S100A7, S100A9, RELA and IL17RE participate in IL-17 signaling pathway; BCL2L13, EIF2AK3 and RELA participate in Mitophapy-animal. Ten genes were selected for florescence quantitative PCR (qPCR) verification and the expression level was consistent with sequencing results. Finally, a control network of SPPA resistance against the H₂O₂-induced KGN cell apoptosis was built based on the target genes screened by the RNA-seq technology. This study provides a direction and some references to further understand the molecular mechanism of SPPA resistance against the H₂O₂-induced KGN cell apoptosis.

Ran GTPase, an eukaryotic gene novelty, is involved in amphioxus mitosis

Ran (ras-related nuclear protein) is a small GTPase belonging to the RAS superfamily that is specialized in nuclear trafficking. Through different accessory proteins, Ran plays key roles in several processes including nuclear import-export, mitotic progression and spindle assembly. Consequently, Ran dysfunction has been linked to several human pathologies. This work illustrates the high degree of amino acid conservation of Ran orthologues across evolution, reflected in its conserved role in nuclear trafficking. Moreover, we studied the evolutionary scenario of the pre-metazoan genetic linkage between Ran and Stx, and we hypothesized that chromosomal proximity of these two genes across metazoans could be related to a regulatory logic or a functional linkage. We studied, for the first time, Ran expression during amphioxus development and reported its presence in the neural vesicle, mouth, gill slits and gut corresponding to body regions involved in active cell division.

Identification and function analysis of ras-related nuclear protein from Macrobrachium rosenbergii involved in Spiroplasma eriocheiris infection

A ras-related nuclear protein (Ran) protein was obtained from Macrobrachium rosenbergii, named MrRan. Phylogenetic analysis results showed that MrRan was clustered in one group together with other crustaceans. Tissue distribution analysis revealed that MrRan was expressed mainly in gill, intestine and stomach, and expressed weakly in muscle. The MrRan expression levels in gill and hemocyte of prawns were significantly up-regulated after challenged by Spiroplasma eriocheiris. The copy number of S. eriocheiris in MrRan dsRNA injection group was significantly less than control groups during infection. Meanwhile, silencing MrRan obviously increased the survival rate of prawns. The subcellular localization experiment suggested that recombinant MrRan was mainly located in the nucleus, and relatively weak in the cytoplasm. Finally, over-expression in Drosophila S2 cell indicated that MrRan could increase copies of S. eriocheiris and decrease of cell viability. The present study suggested that MrRan participated in regulating the phagocytosis of S. eriocheiris in M. rosenbergii.