Degradation of Ndd1 by APC/C(Cdh1) generates a feed forward loop that times mitotic protein accumulation

Nat Commun. 2015 May 11:6:7075. doi: 10.1038/ncomms8075.

Abstract

Ndd1 activates the Mcm1-Fkh2 transcription factor to transcribe mitotic regulators. The anaphase-promoting complex/cyclosome activated by Cdh1 (APC/C(Cdh1)) mediates the degradation of proteins throughout G1. Here we show that the APC/C(Cdh1) ubiquitinates Ndd1 and mediates its degradation, and that APC/C(Cdh1) activity suppresses accumulation of Ndd1 targets. We confirm putative Ndd1 targets and identify novel ones, many of them APC/C(Cdh1) substrates. The APC/C(Cdh1) thus regulates these proteins in a dual manner—both pretranscriptionally and post-translationally, forming a multi-layered feedforward loop (FFL). We predict by mathematical modelling and verify experimentally that this FFL introduces a lag between APC/C(Cdh1) inactivation at the end of G1 and accumulation of genes transcribed by Ndd1 in G2. This regulation generates two classes of APC/C(Cdh1) substrates, early ones that accumulate in S and late ones that accumulate in G2. Our results show how the dual state APC/C(Cdh1) activity is converted into multiple outputs by interactions between its substrates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cdh1 Proteins / genetics
  • Cdh1 Proteins / metabolism*
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Gene Expression Regulation, Fungal / physiology*
  • Mitosis / physiology*
  • Proteolysis
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • CDH1 protein, S cerevisiae
  • Cdh1 Proteins
  • Cell Cycle Proteins
  • NDD1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors