A genomic region transcribed into a long noncoding RNA interacts with the Prss42/Tessp-2 promoter in spermatocytes during mouse spermatogenesis, and its flanking sequences can function as enhancers

• Published in: Molecular reproduction and development 2016-06, Vol.83 (6), p.541-557
• Main Authors: Yoneda, Ryoma, Satoh, Yui, Yoshida, Ikuya, Kawamura, Shohei, Kotani, Tomoya, Kimura, Atsushi P.
• Format: Article
• Language: English
• Subjects: Animals; Enhancer Elements, Genetic; Genetic Loci; Male; Mice; RNA, Long Noncoding - biosynthesis; RNA, Long Noncoding - genetics; Spermatocytes - cytology; Spermatocytes - metabolism; Spermatogenesis - physiology; Transcription, Genetic - physiology; Trypsin - biosynthesis; Trypsin - genetics
• ISSN: 1040-452X; 1098-2795
• DOI: 10.1002/mrd.22650

SUMMARY Spermatogenesis is regulated by many meiotic stage‐specific genes, but how they coordinate the many individual processes is not fully understood. The Prss/Tessp gene cluster is located on mouse chromosome 9F2‐F3, and the three genes at this site (Prss42/Tessp‐2, Prss43/Tessp‐3, and Prss44/Tessp‐4) are specifically activated during meiosis in pachytene spermatocytes. We searched for DNase I hypersensitive sites (HSs) and long noncoding RNAs (lncRNAs) at the Prss/Tessp locus to elucidate how they are activated. We found eight DNase I HSs, three of which were testis germ cell‐specific at or close to the Prss42/Tessp‐2 promoter, and a testis‐specific lncRNA, lncRNA‐HSVIII, that was transcribed from a region adjacent to the Prss42/Tessp‐2 gene. lncRNA‐HSVIII transcripts localized to nuclei of most pachytene spermatocytes and the cytosol of stage‐X pachytene spermatocytes and spermatids. Chromosome conformation capture revealed that the lncRNA‐HSVIII locus specifically interacted with the Prss42/Tessp‐2 promoter in primary and secondary spermatocytes. A 5.8‐kb genome sequence, encompassing the entire lncRNA‐HSVIII sequence and its flanking regions, significantly increased Prss42/Tessp‐2 promoter activity using a reporter‐gene assay, yet this construct did not change lncRNA‐HSVIII expression, indicating that the elevated promoter activity was likely through enhancer activity. Indeed, both upstream and downstream regions of the lncRNA‐HSVIII sequence significantly increased Prss42/Tessp‐2 promoter activity. Our data therefore identified the direct interaction of a genomic region in the lncRNA‐HSVIII locus with the Prss42/Tessp‐2 promoter in spermatocytes, and suggested that sequences adjacent to the lncRNA function as enhancers for the Prss42/Tessp‐2 gene. Mol. Reprod. Dev. 83: 541–557, 2016. © 2016 Wiley Periodicals, Inc.