Staphylococcal nuclease domain-containing protein 1

Staphylococcal nuclease domain-containing protein 1 (SND1) is an endonuclease that mediates the decay of miRNAs in both protein-free and AGO2-associated states, thereby regulating expression of mRNAs involved in cell cycle progression (UniProt: Q7KZF4). Beyond its catalytic role, SND1 functions as a transcriptional coactivator for STAT proteins and participates in viral interactions, including promotion of SARS-CoV-2 RNA synthesis through binding to viral RNA and proteins.

SND1 is expressed across human tissues and participates in fundamental cellular processes including transcriptional regulation and post-transcriptional gene silencing pathways. The UniProt record lists no primary disease associations for this protein.

In Alzheimer's Disease, SND1 is upregulated in post-mortem AD brain relative to age-matched controls, with a mean log2 fold-change of 0.64 across subcellular fractions measured by TMT-labeled proteomics (Chaparral AD proteomics). This elevation suggests potential involvement in AD-associated molecular alterations, though the functional consequences of increased SND1 in AD pathology remain to be elucidated.