Discovery of microRNAs during early spermatogenesis in chicken

Wang

et al. 2018

IJMS

Testis development is a vital and tightly regulated process in mammals. Understanding the biological mechanisms underlying testis development will benefit the animal reproduction industry. Expression changes in microRNA and messenger RNA in response to dynamic regulation effects have been associated with this process. However, very little is known about the roles of these molecules in yak development. Using whole-genome small RNA and messenger RNA sequencing, we performed a comprehensive analysis of the microRNA–messenger RNA interaction network expression in the testicles of Tianzhu white yaks during three developmental stages. Using Short Time-series Expression Miner analysis we identified 589 differentially expressed microRNAs (DERs) and 3383 differentially expressed messenger RNAs (DEGs) in the three age groups. A total of 93 unique DEGs are primarily involved in reproduction and testis development. Subsequently, four integration networks were constructed according to the DEGs and DERs in three biological processes. Nineteen DEGs were potentially regulated by 60 DERs, of which miR-574 and target gene AURKA played a crucial role in yak testis development and reproduction. The results of this study provide a basis for further exploration of the microRNA–messenger RNA interactions in testis development and reproduction and aid in uncovering the molecular mechanisms of spermatogenesis in male mammals.

Section: Discussionmentioning

confidence: 99%

Comprehensive Analysis of MicroRNA–Messenger RNA from White Yak Testis Reveals the Differentially Expressed Molecules Involved in Development and Reproduction

Wang

et al. 2018

IJMS

“…musculus ) [ 29 ] and chicken ( G . gallus ) [ 30 ][ 31 ]. The role of miR-202 in gonads is not yet understood and most of what is known relies on expression data and some functional studies.…”

Section: Introductionmentioning

confidence: 99%

MiR-202 controls female fecundity by regulating medaka oogenesis

et al. 2018

Female gamete production relies on coordinated molecular and cellular processes that occur in the ovary throughout oogenesis. In fish, as in other vertebrates, these processes have been extensively studied both in terms of endocrine/paracrine regulation and protein expression and activity. The role of small non-coding RNAs in the regulation of animal reproduction remains however largely unknown and poorly investigated, despite a growing interest for the importance of miRNAs in a wide variety of biological processes. Here, we analyzed the role of miR-202, a miRNA predominantly expressed in male and female gonads in several vertebrate species. We studied its expression in the medaka ovary and generated a mutant line (using CRISPR/Cas9 genome editing) to determine its importance for reproductive success with special interest for egg production. Our results show that miR-202-5p is the most abundant mature form of the miRNA and that it is expressed in granulosa cells and in the unfertilized egg. The knock out (KO) of mir-202 gene resulted in a strong phenotype both in terms of number and quality of eggs produced. Mutant females exhibited either no egg production or produced a dramatically reduced number of eggs that could not be fertilized, ultimately leading to no reproductive success. We quantified the size distribution of the oocytes in the ovary of KO females and performed a large-scale transcriptomic analysis approach to identified dysregulated molecular pathways. Together, cellular and molecular analyses indicate that the lack of miR-202 impairs the early steps of oogenesis/folliculogenesis and decreases the number of large (i.e. vitellogenic) follicles, ultimately leading to dramatically reduced female fecundity. This study sheds new light on the regulatory mechanisms that control the early steps of follicular development, including possible targets of miR-202-5p, and provides the first in vivo functional evidence that a gonad-predominant microRNA may have a major role in female reproduction.

Reprod Domestic Animals

“…a, b: significant difference among the three species (p < .05) during early stages of spermatogenesis (Buchold et al, 2010), and piRNAs are more abundant in sperm and spermatids (Schubert, 2016). Compared to the well-illustrated mechanisms of spermatogonium development in human (Neto, Bach, Najari, Li, & Goldstein, 2016), poultry (Xu et al, 2017), rodents (Ikami et al, 2015) and some ruminants (Luo, 2014), few contributing factors have been determined to be involved in the sterility of dzo. Thus, we aimed to identify expression profiles of small RNAs in testis of cattle, yak and dzo to determine whether miRNAs and piRNAs differentially expression can be mapped to specific regulation role in development and spermatogenesis.…”

Section: Discussionmentioning

confidence: 99%

Comparative expression profile of microRNAs and piRNAs in three ruminant species testes using next‐generation sequencing

Zhong

Chai

et al. 2018

microRNA (miRNA) and piwi-interacting RNA (piRNA) are two classes small non-coding regulatory RNAs that play crucial roles in multiple biological processes such as spermatogenesis. However, there are no published studies on conjoint analysis of miRNA and piRNA profiles among cattle, yak and their interspecies (the dzo) using sequencing technology. Next-generation sequencing technology was used to profile miRNAs and piRNAs among those three ruminants to elucidate their functions. A total of 119, 14 and six differentially expressed miRNAs were obtained in cattle vs. dzo, cattle vs. yak and yak vs. dzo comparison groups, while there were 873, 1,065 and 1,158 differentially expressed piRNAs in those three comparison groups. The expression of three miRNAs was validated in the three ruminants, and the results suggested that the miRNA expression profiles data could represent actual miRNA expression levels. Moreover, the putative targets of differentially expressed miRNAs were predicted by their own genome, it is worth to note that both the cattle and yak genome were used for dzo, then the targets were subjected to GO enrichment and KEGG pathway analysis, revealing the likely roles for these differentially expressed miRNAs in spermatogenesis. In conclusion, this study provided a useful resource for further elucidation of the miRNAs and piRNAs regulatory roles in spermatogenesis. It may also facilitate the development of therapeutic strategies for dzo reproduction research.