Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents

This Article Full Text (PDF, 202K) PPT slides of all figures Alert me when this article is cited Services Email this article Similar articles in this journal Alert me to new content in the JCB Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by LeBrasseur, N. Search for Related Content PubMed Articles by LeBrasseur, N. Social Bookmarking                            What's this?

© The Rockefeller University Press, 0021-9525/2002/8/384-b $5.00
The Journal of Cell Biology, Volume 158, Number 3, August 5, 2002 384-b-385

Coordination of replication

60S ribosomes do not assemble without Yph1p (bottom). Stillman/Elsevier

A protein found in DNA replication complexes is also essential for ribosome biosynthesis, according to new results from Yi-Chieh Du and Bruce Stillman (Cold Spring Harbor Laboratory, Cold Spring Harbor, NY). The findings imply that the biosynthesis of ribosomes is associated with the decision to enter the cell division cycle.

The authors identified proteins associated with the yeast origin recognition complex (ORC), a set of proteins that binds chromosomal origins of DNA replication. Among the proteins identified was Yph1p, a homologue of zebrafish pescadillo, mutations in which lead to cell proliferation defects. Yph1p was also found in complex with a variety of other proteins, including those involved in ribosome biogenesis, cell cycle regulation, and checkpoint control. "The first link to ribosome biosynthesis came from the finding of Erb1p in the Yph1p complex," says Stillman. "Mutation of the mouse ERB1 orthologue leads to G1 arrest and alters ribosome biosynthesis."

In vivo, Yph1p activity was required for proper 60S ribosome biogenesis and for normal progression during S-phase. Yph1p levels were high in proliferating cells, but declined as cells entered the quiescent phase. Newly synthesized Yph1p was required for cells to exit G₀ and initiate cell division. Though Stillman admits the link between DNA replication and ribosome biosynthesis is speculative, he adds that it makes sense, as proliferation requires the replication of both the genome and the cellular machineries.

Reference:

Du, Y., et al. 2002. Cell. 109:835–848.[CrossRef][Medline]

Nicole LeBrasseur

lebrasn{at}rockefeller.edu

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This Article Full Text (PDF, 202K) PPT slides of all figures Alert me when this article is cited Services Email this article Similar articles in this journal Alert me to new content in the JCB Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by LeBrasseur, N. Search for Related Content PubMed Articles by LeBrasseur, N. Social Bookmarking                            What's this?