RT Journal
A1 Paloviita, Pauliina
A1 Hydén-Granskog, Christel
A1 Yohannes, Dawit A.
A1 Paluoja, Priit
A1 Kere, Juha
A1 Tapanainen, Juha S.
A1 Krjutškov, Kaarel
A1 Tuuri, Timo
A1 Võsa, Urmo
A1 Vuoristo, Sanna
T1 Small RNA expression and miRNA modification dynamics in human oocytes and early embryos
JF Genome Research 
JO Genome Research 
YR 2021 
FD August 01 
VO 31 
IS 8 
SP 1474 
OP 1485 
DO 10.1101/gr.268193.120 
UL http://genome.cshlp.org/content/31/8/1474.abstract 
AB Small noncoding RNAs (sRNAs) play important roles during the oocyte-to-embryo transition (OET), when the maternal phenotype is reprogrammed and the embryo genome is gradually activated. The transcriptional program driving early human development has been studied with the focus mainly on protein-coding RNAs, and expression dynamics of sRNAs remain largely unexplored. We profiled sRNAs in human oocytes and early embryos using an RNA-sequencing (RNA-seq) method suitable for low inputs of material. We show that OET in humans is temporally coupled with the transition from predominant expression of oocyte short piRNAs (os-piRNAs) in oocytes, to activation of microRNA (miRNA) expression in cleavage stage embryos. Additionally, 3′ mono- and oligoadenylation of miRNAs is markedly increased in zygotes. We hypothesize that this may modulate the function or stability of maternal miRNAs, some of which are retained throughout the first cell divisions in embryos. This study is the first of its kind elucidating the dynamics of sRNA expression and miRNA modification along a continuous trajectory of early human development and provides a valuable data set for in-depth interpretative analyses.