RT Journal Article
T1 Feedback regulation of SIN by Etd1 and Rho1 in fission yeast
A1 Alcaide-Gavilán, María
A1 Lahoz, Aurelia
A1 Daga, Rafael
A1 Jiménez, Juan
K1 Etd1
K1 PP2A-Pab1
K1 SIN
K1 Schizosaccharomyces pombe
K1 Spg1
K1 Cytokinesis
K1 Rho1
AB In fission yeast, the septation initiation network (SIN) is thought to promote cytokinesis by downstream activation of Rho1, a conserved GTPase that controls cell growth and division. Here we show that Etd1 and PP2A-Pab1, antagonistic regulators of SIN, are Rho1 regulators. Our genetic and biochemical studies indicate that a C-terminal region of Etd1 may activate Rho1 by directly binding it, whereas an N-terminal domain confers its ability to localize at the growing tips and the division site where Rho1 functions. In opposition to Etd1, our results indicate that PP2A-Pab1 inhibits Rho1. The SIN cascade is upstream-regulated by the Spg1 GTPase. In the absence of Etd1, activity of Spg1 drops down prematurely, thereby inactivating SIN. Interestingly, we find that ectopic activation of Rho1 restores Spg1 activity in Etd1-depleted cells. By using a cytokinesis block strategy, we show that Rho1 is essential to feedback-activate Spg1 during actomyosin ring constriction. Therefore, activation of Spg1 by Rho1, which in turn is regulated by Etd1, uncovers a novel feedback loop mechanism that ensures SIN activity while cytokinesis is progressing.
PB Oxford University Press
YR 2014
FD 2014
LK https://hdl.handle.net/10433/22797
UL https://hdl.handle.net/10433/22797
LA en
NO Genetics. 2014 Feb; 196(2), p.455-70
NO BFU2009-13565 and BFU2010-21310 de el Ministerio de Ciencia e Innovación del Gobierno de España.
NO Departamento de Biología Molecular e Ingeniería Bioquímica
DS RIO
RD May 9, 2026