Virginia Tech researchers reveal maternal, paternal conflicts on a genetic level

frogResearchers within the Biocomplexity Institute of Virginia Tech have demonstrated that eggs actively silence hundreds of paternal genes that encode ribosomal RNA, the protein factories of the cell, and that this suppression is maintained throughout the organism’s life.

The discovery, in Proceedings of the Royal Society B, reveals unorthodox behavior in inheritance and gene expression, including previously unknown conflicts between parental genomes. The information sheds light on cellular processes, evolution, and human disease.

Ribosomal RNA, known as rRNA, is evolutionary one of the most ancient genetic sequences on Earth, presumably preceding even DNA itself, the researchers said. It is central to metabolic health and if damaged can cause severe disease.

The researchers looked to African clawed frogs for insight into rRNA sequences, which generally are excessive, repetitive, and difficult to understand.

“African clawed frogs with their large, complex hybrid genomes are a gold mine for researchers interested in how both genome structure and regulation evolve,” said Pawel Michalak, an associate professor at the Biocomplexity Institute and corresponding author of the study.

In the process of this study, the researchers discovered that maternal genes control rRNA in ways they hadn’t anticipated. Shortly after fertilization, the egg keeps paternal genes from expressing themselves. While the paternal genes are passed down, they remain inactive unless they land on a maternal chromosome.

Originally, the research team was exploring another phenomenon occurring in African clawed frog genomes–nucleolar dominance. The nuleolus assembles ribosomal subunits and generates the rRNA in a cell.

Nucleoli are distinctive nuclear compartments where most rRNA is generated. Nucleolar dominance occurs when hybrid nucleoli are underdeveloped and production of rRNA is thus reduced. Newly generated African clawed frog hybrids between different species have only one nuclelous even though their purebred parents develop two nucleoli.

“To understand the link between maternal control of rRNA and nucleolar dominance will certainly require more work,” said Michalak. “This study aligns with the institute’s new focus in biocomplexity, tying in to research within the institute with RNA.”


UVA Basketball Fans!

uva basketball team of destiny
Team of Destiny: Inside Virginia Basketball’s Run to the 2019 National Championship, by Jerry Ratcliffe and Chris Graham, is available for $25. The book, with additional reporting by Zach Pereles, Scott Ratcliffe, and Scott German, will take you from the aftermath of the stunning first-round loss to UMBC in 2018 through to the thrilling overtime win over Texas Tech to win the 2019 national title, the first in school history.

Dick Vitale on Team of Destiny: “This is a hoops story you will LOVE! Jerry and Chris capture the sensational and dramatic championship journey by Tony Bennett and his tenacious Cavalier team. UVA was Awesome Baby and so is this book!”

Ralph Sampson on Team of Destiny: “Jerry and Chris have lived and seen it all, even before my time. I highly recommend this book to every basketball fan across the globe. This story translates to all who know defeat and how to overcome it!”

Feedback from buyers: “Got the Book in the Mail Saturday, and could not put it down! Great read and great photography as well! Love all of the books I’ve received, but hands down, this is my favorite!” – Russell

Buy here.

augusta free press news
augusta free press news
augusta free press news