Inhibition of zygotic DNA repair in trout: transcriptome analysis of the offspring

ABSTRACT: Zygotic repair of paternal genome is a key event after fertilization. Spermatozoa accumulate DNA single and double strand breaks during spermatogenesis and can suffer additional damage before fertilization by different factors, including cryopreservation. Fertilization with DNA damaged spermatozoa (DDS) is considered to promote implantation failures and abortions, but also long term effects in the progeny that could be related to a defective repair. Base excision repair (BER) pathway is considered the most active in zygotic DNA repair, but healthy oocytes contain enzymes for all repairing pathways. In this study the effects of the inhibition of the BER pathway in the zygote, were analyzed on the progeny obtained after fertilization with differentially DDS. Massive gene expression (37.394 transcripts) was analyzed after hatching using microarrays. Trout oocytes are easily fertilized with DDS and the high prolificacy allows obtaining live progeny even with a high rate of abortions. Results showed that DDS, even if increased the number of abortions, provided normal progeny. Nevertheless, the zygotic inhibition of PARP, upstream the BER pathway, result 810 differentially expressed genes (DEGs) after hatching. DEGs are related to DNA repair, apoptosis, telomere maintenance or growth and development, revealing a scenario of impaired DNA damage signalization and repair. Down-regulation of the apoptotic cascade was noticed, suggesting a selection of embryos tolerant to residual DNA damage during embryo development. Our results suggest a high zygotic capacity to repair paternal DNA damage and reveals changes in the progeny from defective repairing zygotes whose long term consequences should be deeply analyzed Gene expression was analyzed in trout larvae one day after hatching obtained from differentially DNA damaged sperm with or without zygotic inhibition of the BER pathway of DNA repair. Eggs from two females were pooled and fertilized with sperm fresh (F samples) or cryopreserved using different procedures (LDL and EY samples). Ten min later two batches from each sperm kind were treated with 3-aminobenzamide (3AB) to inhibit the PARP activity. Ten larvae per each one of the 6 treatments (3sperm kind x 2 zygotic treatments) were analyzed after pooling RNA. Four replicates per treatment were done fertilizing eggs from the same females with sperm from 4 different males.

ORGANISM(S): Oncorhynchus mykiss

SUBMITTER: Julien Bobe 

PROVIDER: E-GEOD-52217 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress