Table 4.

The available assays of piRNAs

Common Assays	Objective of Assays	Reference
High-throughput Sequencing (HTS)	Assaying new and known piRNAs	[17, 53]
Reverse Transcription-quantitative PCR (RT-qPCR)	Assaying exact piRNA copy number per cell and the relative expression	[22]
Southern Blot	Assaying exact piRNA copy number	[53]
Nouthern Blot	Assaying the number of nucleic acids of piRNA	[22]
RNA binding protein immunoprecipitation (RIP)	Assaying the interaction of piRNA-proteins	[22, 53]
RNA Pull Down
Luciferase reporter system	Assaying the interaction of piRNA-target RNA	[22, 65]
Microarray assay	Assaying DNA methylation by piRNAs,	[45]