Nuclear PP2A-Cdc55 prevents APC-Cdc20 activation during the spindle assembly checkpoint.
نویسندگان
چکیده
Cdc55, a regulatory B-subunit of protein phosphatase 2A (PP2A) complex, is essential for the spindle assembly checkpoint (SAC) in budding yeast, but the regulation and molecular targets of PP2A-Cdc55 have not been clearly defined or are controversial. Here, we show that an important target of Cdc55 in the SAC is the anaphase-promoting complex (APC) coupled with Cdc20 and that APC-Cdc20 is kept inactive by dephosphorylation by nuclear PP2A-Cdc55 when spindle is damaged. By isolating a new class of Cdc55 mutants specifically defective in the SAC and by artificially manipulating nucleocytoplasmic distribution of Cdc55, we further show that nuclear Cdc55 is essential for the SAC. Because the Cdc55-binding proteins Zds1 and Zds2 inhibit both nuclear accumulation of Cdc55 and SAC activity, we propose that spatial control of PP2A by Zds1 family proteins is important for tight control of SAC and mitotic progression.
منابع مشابه
A - Cdc 55 prevents APC - Cdc 20 activation during the spindle assembly checkpoint
Cdc55, a regulatory B-subunit of PP2A complex, is essential for the Spindle Assembly Checkpoint (SAC) in budding yeast, but regulation and molecular targets of PP2A-Cdc55 have not been clearly defined or controversial. Here we show that an important target of Cdc55 in the SAC is Anaphase Promoting Complex (APC) coupled with Cdc20 and that APC-Cdc20 is kept inactive by dephosphorylation by nucle...
متن کاملA - Cdc 55 prevents APC - Cdc 20 activation during the spindle assembly checkpoint ( SAC )
Cdc55, a regulatory B-subunit of PP2A complex, is essential for the Spindle Assembly Checkpoint (SAC) in budding yeast, but regulation and molecular targets of PP2A-Cdc55 have not been clearly defined or controversial. Here we show that an important target of Cdc55 in the SAC is Anaphase Promoting Complex (APC) coupled with Cdc20 and that APC-Cdc20 is kept inactive by dephosphorylation by nucle...
متن کاملAdaptation to the spindle checkpoint is regulated by the interplay between Cdc28/Clbs and PP2ACdc55
The spindle checkpoint arrests cells in metaphase until all chromosomes are properly attached to the chromosome segregation machinery. Thereafter, the anaphase promoting complex (APC/C) is activated and chromosome segregation can take place. Cells remain arrested in mitosis for hours in response to checkpoint activation, but not indefinitely. Eventually, they adapt to the checkpoint and proceed...
متن کاملThe PP2AB56 phosphatase promotes the association of Cdc20 with APC/C in mitosis.
PP2A comprising B56 regulatory subunit isoforms (PP2AB56) is a serine/threonine phosphatase essential for mitosis. At the kinetochore, PP2AB56 both stabilizes microtubule binding and promotes silencing of the spindle assembly checkpoint (SAC) through its association with the SAC protein BubR1. Cells depleted of the B56 regulatory subunits of PP2A are delayed in activation of Cdc20-containing AP...
متن کاملAPC/C- and Mad2-mediated degradation of Cdc20 during spindle checkpoint activation.
The spindle assembly checkpoint (SAC) is an important mechanism that prevents the separation of sister chromatids until the microtubules radiating from the spindle poles are correctly attached to the kinetochores. Cdc20, an activator of the Anaphase Promoting Complex/Cyclosome (APC/C), is known as a major downstream target for inhibition by the SAC through the binding of mitotic checkpoint prot...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of cell science
دوره 126 Pt 19 شماره
صفحات -
تاریخ انتشار 2013