SAP30 targeted by miR-133b was involved in the process of nuclear decondensation in Chinese mitten crab (Eriocheir sinensis) sperm

The aim of this study was to investigate the regulatory role of miR-133b on the expression of Sin3a associated protein 30 (SAP30) during sperm nuclear decondensation. The expressions of both SAP30 at mRNA and protein levels and miRNA targeted into SAP30 were analyzed in the testis tissues of adult and juvenile Eriocheir sinensis, to explore the distribution of SAP30 and the possible regulatory relationship of miRNAs with SAP30, using the high-throughput sequencing, real-time fluorescence quantitative (RT-qPCR), western blot(WB), Immunofluorescence (IF), and other techniques. The results showed that SAP30 was differentially expressed in decondensed nuclei of E. sinensis testis tissue (P < 0.05), and was up-regulated in adult crab testis tissue. The expression at the mRNA level was consistent with the expression at the protein level. miR-133b targeting SAP30 is differentially expressed in adult and juvenile crab testis tissues, but compared with juvenile crab testis tissue, they are all down-regulated in adult crab testis tissue, indicating that SAP30 and miR-133b are highly likely to have Targeting regulatory relationships. SAP30 was mainly located in the nucleus in the testis tissue of E. sinensis, and its expression level was the highest in spermatogonia. With the development of cells, the expression of SAP30 decreased. The SAP30 gene encodes a protein that is a component of the histone deacetylase complex. SAP30 may be involved in the regulation of chromatin dynamics by regulating the level of histone deacetylation, and thus plays an important role in the transition from the relatively condensed state in the early stage to the decondensed state in the late stage of the sperm nucleus of E. sinensis. SAP30 may be a key protein involved in sperm nuclear decondensation, and the reduction of miR-133b may be a key factor promoting the high expression of SAP30 in adult crab testis tissue.

Automated summary

The aim of this study was to investigate the regulatory role of miR-133b on the expression of SAP30 during sperm nuclear decondensation. Using various techniques, the expressions of SAP30 at mRNA and protein levels and miR-133b targeting SAP30 were analyzed in the testis tissues of adult and juvenile Eriocheir sinensis. The results showed that SAP30 was differentially expressed in decondensed nuclei of E. sinensis testis tissue and miR-133b targeting SAP30 was also differentially expressed in adult and juvenile crab testis tissues, indicating a potential regulatory relationship between SAP30 and miR-133b.