A long noncoding RNA binding to QKI-5 regulates germ cell apoptosis via p38 MAPK signaling pathway

Kai Li,Mengzhen Li,Linfang Wang,Shiying Miao,Yan Lu,Shunshun Zhong,Wei Song,Dingfeng Zou,Yahui Li,Yanyun Luo

doi:10.1038/s41419-019-1941-2

Abstract

Spermatogenesis is the complex process of male germline development and requires coordinated interactions by multiple gene products that undergo strict developmental regulations. Increasing evidence has suggested that a number of long noncoding RNAs (lncRNAs) may function as important regulatory molecules in various physiological and pathological processes by binding to specific proteins. Here, we identified a subset of QKI-5-binding lncRNAs in the mouse testis through the integrated analyses of RNA immunoprecipitation (RIP)-microarray and biological verification. Among the lncRNAs, we revealed that NONMMUT074098.2 (Lnc10), which was highly expressed in the spermatogonia and spermatocytes of the testis, interacted with QKI-5. Furthermore, Lnc10 depletion promoted germ cell apoptosis via the activation of p38 MAPK, whereas the simultaneous knockdown of QKI-5 could rescue the apoptotic phenotype and the activation of p38 MAPK, which were induced by the loss of Lnc10. These data indicated that the Lnc10-QKI-5 interaction was associated with the regulatory roles of QKI-5 and that the Lnc10-QKI-5 interaction inhibited the regulation of QKI-5 on the downstream p38 MAPK signaling pathway. Additionally, we functionally characterized the biological roles of Lnc10 and found that the knockdown of Lnc10 promoted the apoptosis of spermatogenic cells in vivo; this suggested that Lnc10 had an important biological role in mouse spermatogenesis. Thus, our study provides a potential strategy to investigate the biological significance of lncRNA-RBP interactions during male germline development.

Highlights

Spermatogenesis refers to the complicated, yet highly ordered, process of continuous production of haploid spermatozoa from diploid spermatogonia, which proceeds through mitosis, meiosis, and spermiogenesis inside the testes[1,2]
We functionally characterized the biological roles of Lnc[10] and found that the knockdown of Lnc[10] promoted the apoptosis of spermatogenic cells in vivo; this suggested that Lnc[10] had an important biological role in mouse spermatogenesis
It has been reported that QKI-5 can selectively interact with multiple RNA species, such as pre-mRNA, microRNA, and circRNA, by binding to the QKI response element (QRE) located in the target RNAs

Summary

Introduction

Spermatogenesis refers to the complicated, yet highly ordered, process of continuous production of haploid spermatozoa from diploid spermatogonia, which proceeds through mitosis, meiosis, and spermiogenesis inside the testes[1,2] This series of processes involves the coordinated interactions of multiple gene products that undergo strict developmental regulations in time and space[3]. LncRNA033862 controls spermatogonial stem cell (SSC) self-renewal and survival by regulating the expression of GDNF receptor alpha[1] (Gfrα1)[14]. Despite these promising findings, most of the lncRNAs systematically identified in the testis have not been functionally characterized in vivo in a mouse model. An integrated analysis of large-scale highthroughput sequencing of immunoprecipitated RNAs after cross-linking (CLIP-Seq) and RNA-Seq datasets respectively identified 21,073 and 1662 lncRNA-RNA binding protein (RBP) interactions in humans and mice[17]

Methods

Results

Conclusion