[miR-362 regulates the proliferation and apoptosis of porcine immature Sertoli cells through targeting the ZNF644 gene].

In testicular tissue, immature Sertoli cell proliferation ability determines the size of mature Sertoli cell populations, which further regulates the spermatogenesis in the adult male animals. Studies have demonstrated that microRNAs (miRNAs) participate in the regulation of the immature Sertoli cell proliferation and apoptosis, but the functions of most identified miRNAs remain unclear. In this study, based on previous RNA-seq results, we analyzed the regulatory role (s) of miR-362 in proliferation and apoptosis of porcine immature Sertoli cells. The ZFN644 gene was predicted to be a target gene of miR-362 using bioinformatics methods. The expression levels of miR-362 and ZNF644 gene were measured using qRT-PCR assay in developing porcine testicular tissues and in immature Sertoli cells transfected with either miR-362 mimic or miR-362 inhibitor. The dual luciferase reporter assay was used to determine the regulatory relationship between miR-362 and ZNF644. The results showed that a putative target site of miR-362 was located in the 3'UTR of ZNF644. The expression of miR-362 was significantly and negatively correlated with ZNF644 expression in the developing porcine testicular tissues. Co-transfection of miR-362 and psiCHECK2-ZNF644-WT 3'UTR luciferase vector significantly suppressed luciferase activity. The ZNF644 gene expression level was significantly regulated by miR-362, demonstrating that miR-362 targets ZNF644 gene and inhibits its expression in porcine immature Sertoli cells. Flow cytometry, CCK8, and EdU assays were used to measure the effects of over-expression of miR-362 or knockdown of ZNF644 on porcine immature Sertoli cell proliferation; Annexin V-FITC/PI staining assays and qRT-PCR technology were used to test the apoptosis and the expression levels of cell survival-related genes, respectively. Over-expression of miR-362 and knockdown of ZNF644 arrested the porcine immature Sertoli cells in G1 and G2 phases of the cell cycle, respectively, and inhibited proliferation, enhanced apoptosis in the porcine immature Sertoli cells, and significantly regulated the expression levels of cell survival-related genes. Taken together, these data indicate that miR-362 inhibits proliferation and promotes apoptosis in porcine immature Sertoli cells by targeting the ZNF644 gene, thereby providing the scientific basis for further study on the function(s) of miR-362 in the porcine spermatogenesis.

The role of ubiquitin-proteasome pathway in spermatogenesis.

Ubiquitin-proteasome pathway (UPP) is the main pathway of protein degradation in eukaryotic cells. The UPP plays very important roles in cell cycle progression, apoptosis, stress response and growth and development through regulating protein interaction, protein activity, protein localization and signal transduction. Previous studies have shown that the UPP is essential for regulating acrosome and tail biogenesis during spermatogenesis in human and animals. The dysregulation of UPP during spermatogenesis results in sperm deformity and reduced sperm motility and leads to reproductive system diseases such as oligospermatism, infertility and testicular tumors. In this review, we summarized the signal transduction and regulation mechanism of UPP in spermatogenesis, which may provide references for future studies.

The complete mitochondrial genome of Xiangdong black goat (Capra hircus).

Xiangdong black goat (Capra hircus) is a native breed of Hunan province in China. It is the first time that the complete mitochondrial genome sequence of Xiangdong black goat is reported in this work, which is determined through the PCR-based method. The total length of the mitognome is 16,641 bp, which contains 2 ribosomal RNA genes, 22 tRNA genes, 13 PCGs and 1 conntrol region (D-loop region). The total base composition of Lantang pig mitochondrial genome is 33.53% A, 13.12% G, 27.25% T and 26.09% C, in the order A > T > C > G. The complete mitochondrial genome of Xiangdong black goat provides an important data in genetic mechanism and the evolution genomes.

The complete sequence of the mitochondrial genome of Dahuabai pig (SusScrofa).

Dahuabai pig is one of the most important indigenous breed of the Guangzhou province of China. It is the first time that the complete mitochondrial genome sequence of Dahuabai pig is reported in this work, which is determined through the PCR-based method. The total length of the mitognome is 16,709 bp, which contains a control region (D-loop region), 2 ribosomal RNA genes, 13 protein-coding genes and 22 tRNA genes. The total base composition of Dahuabai pig mitochondrial genome is 34.68% for A, 26.20% for C, 25.81% for T and 13.32% for G, in the order A > C > T > G. The complete mitochondrial genome of Dahuabai pig provides an important data in studying mitochondrial DNA's role in the process of metabolism and programmed cell death.

The complete mitochondrial genome of Jintang black goat (Capra hircus).

Jintang black goat (Capra hircus) is an indigenous breed of Sichuan province of China. It is the first time that the complete mitochondrial genome sequence of Jintang black goat is reported in this work, which is determined through the PCR-based method. The total length of the mitogenome is 16,813 bp, which contains two ribosomal RNA genes, 22 tRNA genes, 13 PCGs, and a control region (D-loop region). The total base composition of Jintang black goat mitochondrial genome is 33.52% A, 13.13% G, 27.35% T, and 26.00% C, and in the order A > T > C > G. The complete mitochondrial genome of Jintang black goat provides an important data in genetic mechanism and the evolution genomes.

[Research advances in molecular ecology of ammonia oxidizing bacteria].

Ammonia oxidizing bacteria (AOB) play an important role in global nitrogen cycle. This paper reviewed the research advances on molecular ecology of ammonia oxidizing bacteria. The analysis of systematic evolution of AOB based on 16S rRNA reveals that the evolution of AOB is quite simple, which belongs to beta and gamma subgroup of Proteobacteria. This paper also introduced the main molecular ecological methods in the study of AOB, which included denature gradient gel electrophoresis (DGGE), terminal restriction fragment length polymorphism (T-RFLP), fluorescence in situ hybridization (FISH), and real-time PCR, summarized the effects of ecological factors on the communities and populations of AOB, and prospected the research directions on molecular ecology of AOB.