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

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.

doi:10.1101/2020.08.06.240200

bioRxiv · 10.1101/2020.08.06.240200

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

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.

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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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