Spermatogenesis is a continual process that occurs in the testes, in which diploid spermatogonial stem cells (SSCs) differentiate and generate haploid spermatozoa. This highly efficient and intricate process is orchestrated at multiple levels. N⁶-methyladenosine (m⁶A), an epigenetic modification prevalent in mRNAs, is implicated in the transcriptional regulation during spermatogenesis. However, the dynamics of m⁶A modification in non-rodent mammalian species remains unclear. Here, we systematically investigated the profile and role of m⁶A during spermatogenesis in pigs. By analyzing the transcriptomic distribution of m⁶A in spermatogonia, spermatocytes, and round spermatids, we identified a globally conserved m⁶A pattern between porcine and murine genes with spermatogenic function. We found that m⁶A was enriched in a group of genes that specifically encode the metabolic enzymes and regulators. In addition, transcriptomes in porcine male germ cells could be subjected to the m⁶A modification. Our data show that m⁶A plays the regulatory roles during spermatogenesis in pigs, which is similar to that in mice. Illustrations of this point are three genes (SETDB1, FOXO1, and FOXO3) that are crucial to the determination of the fate of SSCs. To the best of our knowledge, this study for the first time uncovers the expression profile and role of m⁶A during spermatogenesis in large animals and provides insights into the intricate transcriptional regulation underlying the lifelong male fertility in non-rodent mammalian species.
Animals ; Male ; Mice ; Cell Differentiation/genetics* ; Mammals/metabolism* ; Methylation ; RNA, Messenger/metabolism* ; Spermatogenesis/genetics* ; Spermatozoa/metabolism* ; Swine/genetics* ; Testis/metabolism* ; Transcriptome ; RNA Methylation/genetics*

Stress granules (SGs) are cytoplasmic ribonucleoprotein assemblies formed under stress conditions and are related to various biological processes and human diseases. Previous studies have reported the regulatory role of some proteins and linear RNAs in SG assembly. However, the relationship between circular RNAs (circRNAs) and SGs has not been discovered. Here, we screened both linear RNAs and circRNAs in SGs using improved total RNA sequencing of purified SG cores in mammalian cells and identified circular transcripts specifically localized in SGs. circRNAs with higher SG-related RNA-binding protein (RBP) binding abilities are more likely to be enriched in SGs. Furthermore, some SG-enriched circRNAs are differentially expressed in hepatocellular carcinoma (HCC) and adjacent tissues. These results suggest the regulatory role of circRNAs in SG formation and provide insights into the biological function of circRNAs and SGs in HCC.
Animals ; Humans ; RNA, Circular/metabolism* ; Carcinoma, Hepatocellular/metabolism* ; Stress Granules ; Cytoplasmic Granules/metabolism* ; Liver Neoplasms/metabolism* ; RNA/metabolism* ; Stress, Physiological/genetics* ; Mammals/genetics*

N⁶-methyladenine (m⁶A) is the most abundant RNA modification in mammalian messenger RNAs (mRNAs), which participates in and regulates many important biological activities, such as tissue development and stem cell differentiation. Due to an improved understanding of m⁶A, researchers have discovered that the biological function of m⁶A can be linked to many stages of mRNA metabolism and that m⁶A can regulate a variety of complex biological processes. In addition to its location on mammalian mRNAs, m⁶A has been identified on viral transcripts. m⁶A also plays important roles in the life cycle of many viruses and in viral replication in host cells. In this review, we briefly introduce the detection methods of m⁶A, the m⁶A-related proteins, and the functions of m⁶A. We also summarize the effects of m⁶A-related proteins on viral replication and infection. We hope that this review provides researchers with some insights for elucidating the complex mechanisms of the epitranscriptome related to viruses, and provides information for further study of the mechanisms of other modified nucleobases acting on processes such as viral replication. We also anticipate that this review can stimulate collaborative research from different fields, such as chemistry, biology, and medicine, and promote the development of antiviral drugs and vaccines.
Animals ; Viruses/genetics* ; RNA, Messenger/metabolism* ; Adenosine/metabolism* ; Cell Differentiation ; Mammals/metabolism*

Although the function of tRNAs in the translational process is well established, it remains controversial whether tRNA abundance is tightly associated with translational efficiency (TE) in mammals. Moreover, how critically the expression of tRNAs contributes to the establishment of tissue-specific proteomes in mammals has not been well addressed. Here, we measured both tRNA expression using demethylase-tRNA sequencing (DM-tRNA-seq) and TE of mRNAs using ribosome-tagging sequencing (RiboTag-seq) in the brain, heart, and testis of mice. Remarkable variation in the expression of tRNA isodecoders was observed among different tissues. When the statistical effect of isodecoder-grouping on reducing variations is considered through permutating the anticodons, we observed an expected reduction in the variation of anticodon expression across all samples, an unexpected smaller variation of anticodon usage bias, and an unexpected larger variation of tRNA isotype expression at amino acid level. Regardless of whether or not they share the same anticodons, the isodecoders encoding the same amino acids are co-expressed across different tissues. Based on the expression of tRNAs and the TE of mRNAs, we find that the tRNA adaptation index (tAI) and TE are significantly correlated in the same tissues but not between tissues; and tRNA expression and the amino acid composition of translating peptides are positively correlated in the same tissues but not between tissues. We therefore hypothesize that the tissue-specific expression of tRNAs might be due to post-transcriptional mechanisms. This study provides a resource for tRNA and translation studies, as well as novel insights into the dynamics of tRNAs and their roles in translational regulation.
Animals ; Mice ; Anticodon/genetics* ; Transcriptome ; Protein Biosynthesis ; RNA, Transfer/chemistry* ; Amino Acids/metabolism* ; Mammals/metabolism*

This study aims to investigate the role of slient mating-type information regulation 2 homolog 1(SIRT1)/tuberous sclerosis complex 2(TSC2)/mammalian target of rapamycin(mTOR) signaling pathways in the Periplaneta americana extract CⅡ-3-induced senescence of human leukemia K562 cells. K562 cells were cultured in vitro and treated with 0(control), 5, 10, 20, 40, 80, and 160 μg·mL~(-1) of P. americana extract CⅡ-3. Cell counting kit-8(CCK-8) and flow cytometry were employed to examine the proliferation and cell cycle of the K562 cells. Senescence-associated β-galactosidase stain kit(SA-β-gal) was used to detect the positive rate of senescent cells. Mitochondrial membrane potential was detected by flow cytometry. The relative mRNA level of telomerase reverse transcriptase(TERT) was determined by fluorescence quantitative PCR. The mRNA and protein levels of SIRT1, TSC2, and mTOR were determined by fluorescence quantitative PCR and Western blot, respectively. The results showed that CⅡ-3 significantly inhibited the proliferation of K562 cells and the treatment with 80 μg·mL~(-1) CⅡ-3 for 72 h had the highest inhibition rate. Therefore, 80 μg·mL~(-1) CⅡ-3 treatment for 72 h was selected as the standard for subsequent experiments. Compared with the control group, CⅡ-3 increased the proportion of cells arrested in G_0/G_1 phase, decreased the proportion of cells in S phase, increased the positive rate of SA-β-Gal staining, elevated the mitochondrial membrane potential and down-regulated the mRNA expression of TERT. Furthermore, the mRNA expression of SIRT1 and TSC2 was down-regulated, while the mRNA expression of mTOR was up-regulated. The protein expression of SIRT1 and p-TSC2 was down-regulated, while the protein expression of p-mTOR was up-regulated. The results indicated that P. americana extract CⅡ-3 induced the senescence of K562 cells via the SIRT1/mTOR signaling pathway.
Humans ; Animals ; Periplaneta ; Sirtuin 1/genetics* ; K562 Cells ; Signal Transduction ; TOR Serine-Threonine Kinases/genetics* ; RNA, Messenger ; Mammals

The present study aimed to investigate the protective role of Shaofu Zhuyu Decoction(SFZY) against endometriosis fibrosis in mice, and decipher the underlying mechanism through the phosphatase and tensin homolog deleted on chromosome ten(PTEN)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) pathway. Eighty-five BALB/c female mice were randomly assigned into a blank group, a model group, high-, medium, and low-dose SFZY(SFZY-H, SFZY-M, and SFZY-L, respectively) groups, and a gestrinone suspension(YT) group. The model of endometriosis was induced by intraperitoneal injection of uterine fragments. The mice in different groups were administrated with corresponding groups by gavage 14 days after modeling, and the blank group and model group with equal volume of distilled water by gavage. The treatment lasted for 14 days. The body weight, paw withdrawal latency caused by heat stimuli, and total weight of dissected ectopic focus were compared between different groups. The pathological changes of the ectopic tissue were observed via hematoxylin-eosin(HE) and Masson staining. Real-time PCR was employed to measure the mRNA levels of α-smooth muscle actin(α-SMA) and collagen type Ⅰ(collagen-Ⅰ) in the ectopic tissue. The protein levels of PTEN, Akt, mTOR, p-Akt, and p-mTOR in the ectopic tissue were determined by Western blot. Compared with the blank group, the modeling first decreased and then increased the body weight of mice, increased the total weight of ectopic focus, and shortened the paw withdrawal latency. Compared with the model group, SFZY and YT increased the body weight, prolonged the paw withdrawal latency, and decreased the weight of ectopic focus. Furthermore, the drug administration, especially SFZY-H and YT(P<0.01), recovered the pathological and reduced the area of collagen deposition. Compared with the blank group, the modeling up-regulated the mRNA levels of α-SMA and collagen-Ⅰ in the ectopic focus, and such up-regulation was attenuated after drug intervention, especially in the SFZY-H and YT groups(P<0.05,P<0.01). Compared with the blank group, the modeling down-regulated the protein level of PTEN and up-regulated the protein levels of Akt, mTOR, p-Akt, and p-mTOR(P<0.01, P<0.001). Drug administration, especially SFZY-H and YT, restored such changes(P<0.01). SFZY may significantly attenuate the focal fibrosis in the mouse model of endometriosis by regulating the PTEN/Akt/mTOR signaling pathway.
Female ; Animals ; Mice ; Humans ; Proto-Oncogene Proteins c-akt/genetics* ; Choristoma ; Endometriosis/genetics* ; TOR Serine-Threonine Kinases/genetics* ; RNA, Messenger ; Signal Transduction ; Body Weight ; Mammals ; PTEN Phosphohydrolase/genetics*

Atoh1 gene encodes a helix-loop-helix transcription factor which is involved in the generation and differentiation of mammalian auditory hair cells and supporting cells, and regulation of the proliferation of cochlear cells, therefore plays an important role in the pathogenesis and recovery of sensorineural deafness. This study reviews the progress of the Atoh1 gene in hair cell regeneration, with the aim of providing a reference for the study of hair cell regeneration gene therapy for sensorineural deafness.
Animals ; Humans ; Basic Helix-Loop-Helix Transcription Factors/genetics* ; Hair Cells, Auditory/physiology* ; Transcription Factors ; Hearing Loss, Sensorineural ; Cell Differentiation ; Deafness ; Regeneration/genetics* ; Mammals

Mammalian testis exhibits remarkably high transcriptome complexity, and spermatogenesis undergoes two periods of transcriptional cessation. These make the RNA-binding proteins (RBPs) the utmost importance during male germ cell development. Heterogeneous nuclear ribonucleoproteins (hnRNPs) are a large family of RBPs implicated in many steps of RNA processing; however, their roles in spermatogenesis are largely unknown. Here, we investigated the expression pattern of 12 hnRNP family members in mouse testes and found that most detected members are highly expressed in the testis. Furthermore, we found that most of the detected hnRNP proteins (hnRNPD, hnRNPK, hnRNPQ, hnRNPU, and hnRNPUL1) display the highest signals in the nuclei of pachytene spermatocytes, round spermatids, and Sertoli cells, whereas hnRNPE1 exclusively concentrates in the manchette of elongating spermatids. The expression of these hnRNP proteins showed both similarities and specificity, suggesting their diverse roles in spermatogenesis.
Mice ; Male ; Animals ; Heterogeneous-Nuclear Ribonucleoproteins/metabolism* ; Spermatogenesis/genetics* ; Testis/metabolism* ; Spermatids/metabolism* ; Sertoli Cells ; Spermatocytes/metabolism* ; RNA-Binding Proteins/metabolism* ; Mammals

OBJECTIVE: To investigate the role of hippocampal neurodevelopment in the antidepressant effect of baicalin. METHODS: Forty male Institute of Cancer Research mice were divided into control, corticosterone (CORT, 40 mg/kg), CORT+baicalin-L (25 mg/kg), CORT+baicalin-H (50 mg/kg), and CORT+fluoxetine (10 mg/kg) groups according to a random number table. An animal model of depression was established by chronic CORT exposure. Behavioral tests were used to assess the reliability of depression model and the antidepressant effect of baicalin. In addition, Nissl staining and immunofluorescence were used to evaluate the effect of baicalin on hippocampal neurodevelopment in mice. The protein and mRNA expression levels of neurodevelopment-related factors were detected by Western blot analysis and real-time polymerase chain reaction, respectively. RESULTS: Baicalin significantly ameliorated the depressive-like behavior of mice resulting from CORT exposure and promoted the development of dentate gyrus in hippocampus, thereby reversing the depressive-like pathological changes in hippocampal neurons caused by CORT neurotoxicity. Moreover, baicalin significantly decreased the protein and mRNA expression levels of glycogen synthase kinase 3β (GSK3β), and upregulated the expression levels of cell cycle protein D1, p-mammalian target of rapamycin (mTOR), doublecortin, and brain-derived neurotrophic factor (all P<0.01). There were no significant differences between baicalin and fluoxetine groups (P>0.05). CONCLUSION Baicalin can promote the development of hippocampal neurons via mTOR/GSK3β signaling pathway, thus protect mice against CORT-induced neurotoxicity and play an antidepressant role.
Male ; Animals ; Mice ; Corticosterone ; Fluoxetine/metabolism* ; Depression/chemically induced* ; Glycogen Synthase Kinase 3 beta/metabolism* ; Reproducibility of Results ; Antidepressive Agents/pharmacology* ; Hippocampus ; TOR Serine-Threonine Kinases/metabolism* ; RNA, Messenger/genetics* ; Behavior, Animal ; Disease Models, Animal ; Mammals/metabolism*

To compare the pancreatic proteomics and autophagy between Rehmanniae Radix-and Rehmanniae Radix Praeparata-treated mice with type 2 diabetes mellitus(T2DM). The T2DM mouse model was established by high-fat diet coupled with streptozotocin(STZ, intraperitoneal injection, 100 mg·kg~(-1), once a day for three consecutive days). The mice were then randomly assigned into a control group, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) catalpol groups, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix Praeparata groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) 5-hydroxymethyl furfuraldehyde(5-HMF) groups, and a metformin(250 mg·kg~(-1)) group. In addition, a normal group was also set and each group included 8 mice. The pancreas was collected after four weeks of administration and proteomics tools were employed to study the effects of Rehmanniae Radix and Rehmanniae Radix Praeparata on protein expression in the pancreas of T2DM mice. The expression levels of proteins involved in autophagy, inflammation, and oxidative stress response in the pancreatic tissues of T2DM mice were determined by western blotting, immunohistochemical assay, and transmission electron microscopy. The results showed that the differential proteins between the model group and Rehmanniae Radix/Rehmanniae Radix Prae-parata group were enriched in 7 KEGG pathways, such as autophagy-animal, which indicated that the 7 pathways may be associated with T2DM. Compared with the control group, drug administration significantly up-regulated the expression levels of beclin1 and phosphorylated mammalian target of rapamycin(p-mTOR)/mTOR and down-regulated those of the inflammation indicators, Toll-like receptor-4(TLR4) and Nod-like receptor protein 3(NLRP3), in the pancreas of T2DM mice, and Rehmanniae Radix showed better performance. In addition, the expression levels of inducible nitric oxide synthase(iNOS), nuclear factor erythroid 2-related factor 2(Nrf2), and heine oxygenase-1(HO-1) in the pancreas of T2DM mice were down-regulated after drug administration, and Rehmanniae Radix Praeparata demonstrated better performance. The results indicate that both Rehmanniae Radix and Rehmanniae Radix Praeparata can alleviate the inflammatory symptoms, reduce oxidative stress response, and increase the autophagy level in the pancreas of T2DM mice, while they exert the effect on different autophagy pathways.
Mice ; Animals ; Diabetes Mellitus, Type 2/genetics* ; Streptozocin/pharmacology* ; Diet, High-Fat/adverse effects* ; Proteomics ; Inflammation ; TOR Serine-Threonine Kinases ; Autophagy ; Mammals