The process of formation of spermatozoa, including spermatocytogenesis and spermiogenesis.

Any process by which an organism or tissue maintains a population of germ-line stem cells.

Any process in which RNA molecules inactivate expression of target genes.

The chemical reactions and pathways involving piRNAs, Piwi-associated RNAs, a class of 24- to 30-nucleotide RNA derived from repeat or complex DNA sequence elements and processed by a Dicer-independent mechanism.

Any process that stops, prevents, or reduces the frequency, rate or extent of cellular DNA-templated transcription.

Any process that modulates the rate, frequency, or extent of the downregulation of gene expression through the action of microRNAs (miRNAs), endogenous 21-24 nucleotide small RNAs processed from stem-loop RNA precursors (pre-miRNAs). Once incorporated into a RNA-induced silencing complex (RISC), miRNAs can downregulate gene expression by either of two posttranscriptional mechanisms: RNA (often mRNA) cleavage or mRNA translational repression.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.

A small cytoplasmic, non-membranous RNA/protein complex aggregates in the primordial germ cells of many higher eukaryotes.

Cytoplasm situated near, or occurring around, the nucleus.