Biology subjects

Ono, R.

Publications and source records attributed to Ono, R..

2 recordsLinked to original sources

bioRxiv2021

Ancient genomes from the last three millennia support multiple human dispersals into Wallacea

Previous research indicates that the human genetic diversity found in Wallacea - islands in present-day Eastern Indonesia and Timor-Leste that were never part of the Sunda or Sahul continental shelves - has been shaped by complex interactions between migrating Austronesian farmers and indigenous hunter-gatherer communities. Here, we provide new insights into this regions demographic history based on genome-wide data from 16 ancient individuals (2600-250 yrs BP) from islands of the North Moluccas, Sulawesi, and East Nusa Tenggara. While the ancestry of individuals from the northern islands fit earlier views of contact between groups related to the Austronesian expansion and the first colonization of Sahul, the ancestry of individuals from the southern islands revealed additional contributions from Mainland Southeast Asia, which seems to predate the Austronesian admixture in the region. Admixture time estimates for the oldest individuals of Wallacea are closer to archaeological estimates for the Austronesian arrival into the region than are admixture time estimates for present-day groups. The decreasing trend in admixture times exhibited by younger individuals supports a scenario of multiple or continuous admixture involving Papuan- and Asian-related groups. Our results clarify previously debated times of admixture and suggest that the Neolithic dispersals into Island Southeast Asia are associated with the spread of multiple genetic ancestries.

genomics↗

bioRxiv2021

PEG10 viral aspartic protease domain is essential for the maintenance of fetal capillary structure in the mouse placenta

The therian-specific gene paternally expressed 10 (Peg10) plays an essential role in placenta formation: Peg10 knockout (KO) mice exhibit early embryonic lethality due to severe placental defects. The PEG10 protein exhibits homology to long terminal repeat (LTR) retrotransposon GAG and POL proteins, therefore mice harboring a mutation in its highly conserved viral aspartic protease motif in the POL-like region were generated because it is essential for LTR retrotransposons/retroviruses. Intriguingly, frequent perinatal lethality, not early embryonic lethality, was observed with fetal and placental growth retardation starting mid-gestation. In the mutant placentas, severe defects were observed in the fetal vasculature, where PEG10 is expressed in the three trophoblast cell layers that surround fetal capillary endothelial cells. Thus, Peg10 has essential roles not only in early placenta formation, but also in placental vasculature maintenance from mid- to late-gestation. This implies that along the feto-maternal placenta interface an interaction occurs between two retrovirus-derived genes, Peg10 and retrotransposon Gag like 1 (Rtl1, also called Peg11), that is essential for the maintenance of fetal capillary endothelial cells. Summary statementDisruption of the highly conserved viral aspartic protease domain in PEG10 causes placental abnormality leading to perinatal lethality in mice.

developmental biology↗