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bioRxiv · 10.1101/2020.08.06.240200

SNPC-1.3 is a sex-specific transcription factor that drives male piRNA expression in C. elegans

Abstract

Piwi-interacting RNAs (piRNAs) play essential roles in silencing repetitive elements to promote fertility in metazoans. Studies in worms, flies, and mammals reveal that piRNAs are expressed in a sex-specific manner. However, the mechanisms underlying this sex-specific regulation are unknown. Here we identify SNPC-1.3, a variant of a conserved subunit of the snRNA activating protein complex, as a male-specific piRNA transcription factor in C. elegans. Binding of SNPC-1.3 at male piRNA loci drives spermatogenic piRNA transcription and requires the core piRNA transcription factor SNPC-4. Loss of snpc-1.3 leads to depletion of male piRNAs and defects in male-dependent fertility. Furthermore, TRA-1, a master regulator of sex determination, binds to the snpc-1.3 promoter and represses its expression during oogenesis. Loss of TRA-1 targeting causes ectopic expression of snpc-1.3 and male piRNAs during oogenesis. Thus, sexual dimorphic regulation of snpc-1.3 coordinates male and female piRNA expression during germline development.

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Choi, C. P., Tay, R. J., Starostik, M. R., Feng, S., Moresco, J. J., Montgomery, B. E., Xu, E., Hammond, M. A., Schatz, M. C., Montgomery, T. A., Yates, J. R., Jacobsen, S. E., Kim, J. K.. 2020-08-06. SNPC-1.3 is a sex-specific transcription factor that drives male piRNA expression in C. elegans. https://doi.org/10.1101/2020.08.06.240200

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