Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology
RESEARCH ARTICLE

Identification of differentially expressed placental transcripts during multiple gestations in the Eurasian beaver (Castor fiber L.)

A. Lipka A B E , L. Paukszto C , M. Majewska D , J. P. Jastrzebski C , K. Myszczynski C , G. Panasiewicz A and B. Szafranska A
+ Author Affiliations
- Author Affiliations

A Department of Animal Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str 1A, 10-719 Olsztyn-Kortowo, Poland.

B Department of Gynecology and Obstetrics, Faculty of Medical Sciences, University of Warmia and Mazury in Olsztyn, Niepodleglosci Str 44, 10-045 Olsztyn, Poland.

C Department of Plant Physiology, Genetics and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str 1A, 10-719 Olsztyn-Kortowo, Poland.

D Department of Human Physiology, Faculty of Medical Sciences, University of Warmia and Mazury in Olsztyn, Warszawska Str 30, 10-082 Olsztyn, Poland.

E Corresponding author. Email: aleksandra.lipka@uwm.edu.pl

Reproduction, Fertility and Development - https://doi.org/10.1071/RD16186
Submitted: 4 May 2016  Accepted: 22 December 2016   Published online: 14 February 2017

Abstract

The Eurasian beaver is one of the largest rodents that, despite its high impact on the environment, is a non-model species that lacks a reference genome. Characterising genes critical for pregnancy outcome can serve as a basis for identifying mechanisms underlying effective reproduction, which is required for the success of endangered species conservation programs. In the present study, high-throughput RNA sequencing (RNA-seq) was used to analyse global changes in the Castor fiber subplacenta transcriptome during multiple pregnancy. De novo reconstruction of the C. fiber subplacenta transcriptome was used to identify genes that were differentially expressed in placentas (n = 5) from two females (in advanced twin and triple pregnancy). Analyses of the expression values revealed 124 contigs with significantly different expression; of these, 55 genes were identified using MegaBLAST. Within this group of differentially expressed genes (DEGs), 18 were upregulated and 37 were downregulated in twins. Most DEGs were associated with the following gene ontology terms: cellular process, single organism process, response to stimulus, metabolic process and biological regulation. Some genes were also assigned to the developmental process, the reproductive process or reproduction. Among this group, four genes (namely keratin 19 (Krt19) and wingless-type MMTV integration site family – member 2 (Wnt2), which were downregulated in twins, and Nik-related kinase (Nrk) and gap junction protein β2 (Gjb2), which were upregulated in twins) were assigned to placental development and nine (Krt19, Wnt2 and integrin α7 (Itga7), downregulated in twins, and Nrk, gap junction protein β6 (Gjb6), GATA binding protein 6 (Gata6), apolipoprotein A-I (ApoA1), apolipoprotein B (ApoB) and haemoglobin subunit α1 (HbA1), upregulated in twins) were assigned to embryo development. The results of the present study indicate that the number of fetuses affects the expression profile in the C. fiber subplacental transcriptome. Enhancement of transcriptomic resources for C. fiber will improve understanding of the pathways relevant to proper placental development and successful reproduction.

Additional keywords: de novo assembly, differentially expressed genes, pregnancy, RNA-seq.


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