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Hsp90-Associated Immunophilin Homolog Cpr7 Is Required for the Mitotic Stability of [URE3] Prion in Saccharomyces cerevisiae.

Kumar N, Gaur D, Gupta A, Puri A, Sharma D - PLoS Genet. (2015)

Bottom Line: We show that Cpr7 interacts with Ure2 and enhances its fibrillation.The requirement of Cpr7 is specific for [URE3] as its deletion does not antagonize both strong and weak variant of another yeast prion [PSI+], suggesting a distinct role of the Hsp90 co-chaperone with different yeast prions.Our data show that, similar to the Hsp70 family, the Hsp90 chaperones also influence yeast prion maintenance, and that immunophilins could regulate protein multimerization independently of their activity as peptidyl-prolyl isomerases.

View Article: PubMed Central - PubMed

Affiliation: Council of Scientific and Industrial Research-Institute of Microbial Technology, Chandigarh, India.

ABSTRACT
The role of Hsp70 chaperones in yeast prion propagation is well established. Highly conserved Hsp90 chaperones participate in a number of cellular processes, such as client protein maturation, protein degradation, cellular signalling and apoptosis, but little is known about their role in propagation of infectious prion like aggregates. Here, we examine the influence of Hsp90 in the maintenance of yeast prion [URE3] which is a prion form of native protein Ure2, and reveal a previously unknown role of Hsp90 as an important regulator of [URE3] stability. We show that the C-terminal MEEVD pentapeptide motif, but not the client maturation activity of Hsp90, is essential for [URE3] prion stability. In testing deletions of various Hsp90 co-chaperones known to bind this motif, we find the immunophilin homolog Cpr7 is essential for [URE3] propagation. We show that Cpr7 interacts with Ure2 and enhances its fibrillation. The requirement of Cpr7 is specific for [URE3] as its deletion does not antagonize both strong and weak variant of another yeast prion [PSI+], suggesting a distinct role of the Hsp90 co-chaperone with different yeast prions. Our data show that, similar to the Hsp70 family, the Hsp90 chaperones also influence yeast prion maintenance, and that immunophilins could regulate protein multimerization independently of their activity as peptidyl-prolyl isomerases.

No MeSH data available.


Related in: MedlinePlus

Cns1 complements Cpr7 function required for [URE3] stability.The cpr7Δ strain was transformed with pRS426PCNS1-CNS1 or pRS413PTEF-CPR7, and [URE3] was monitored on ½ YPD plates as described before. All colonies harbouring the Cns1 encoding plasmid show white colony color suggesting functional redundancy of Cns1 and Cpr7 with regard to [URE3] propagation.
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pgen.1005567.g005: Cns1 complements Cpr7 function required for [URE3] stability.The cpr7Δ strain was transformed with pRS426PCNS1-CNS1 or pRS413PTEF-CPR7, and [URE3] was monitored on ½ YPD plates as described before. All colonies harbouring the Cns1 encoding plasmid show white colony color suggesting functional redundancy of Cns1 and Cpr7 with regard to [URE3] propagation.

Mentions: Cns1 is unique among the known TPR containing Hsp90 co-chaperones in being essential for yeast cell growth. The 385 amino acid protein contains three TPR motifs and is a suppressor of the growth defect caused by cpr7Δ, which suggests partial functional redundancy between Cpr7 and Cns1 [55]. In order to explore whether Cns1 complements for the loss of Cpr7 with regard to [URE3], a plasmid encoding Cns1 (pRS426PCNS1-CNS1) was transformed into cpr7Δ cells pooled from Ade- medium and transformants were further monitored for [URE3] propagation as described above for Cpr6. As seen before, cells expressing Cpr7 from the constitutive TEF promoter showed stable [URE3] on ½YPD (Fig 5). As expected, cells that lost the Cpr7-encoding plasmid (no growth on histidine deficient medium) show red colony color and no growth on Ade- medium. As we saw for Cpr7, we found that cells that express Cns1 are white and grow normally on plates lacking adenine, suggesting that Cns1 functionally complements Cpr7 with regard to [URE3] propagation.


Hsp90-Associated Immunophilin Homolog Cpr7 Is Required for the Mitotic Stability of [URE3] Prion in Saccharomyces cerevisiae.

Kumar N, Gaur D, Gupta A, Puri A, Sharma D - PLoS Genet. (2015)

Cns1 complements Cpr7 function required for [URE3] stability.The cpr7Δ strain was transformed with pRS426PCNS1-CNS1 or pRS413PTEF-CPR7, and [URE3] was monitored on ½ YPD plates as described before. All colonies harbouring the Cns1 encoding plasmid show white colony color suggesting functional redundancy of Cns1 and Cpr7 with regard to [URE3] propagation.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4608684&req=5

pgen.1005567.g005: Cns1 complements Cpr7 function required for [URE3] stability.The cpr7Δ strain was transformed with pRS426PCNS1-CNS1 or pRS413PTEF-CPR7, and [URE3] was monitored on ½ YPD plates as described before. All colonies harbouring the Cns1 encoding plasmid show white colony color suggesting functional redundancy of Cns1 and Cpr7 with regard to [URE3] propagation.
Mentions: Cns1 is unique among the known TPR containing Hsp90 co-chaperones in being essential for yeast cell growth. The 385 amino acid protein contains three TPR motifs and is a suppressor of the growth defect caused by cpr7Δ, which suggests partial functional redundancy between Cpr7 and Cns1 [55]. In order to explore whether Cns1 complements for the loss of Cpr7 with regard to [URE3], a plasmid encoding Cns1 (pRS426PCNS1-CNS1) was transformed into cpr7Δ cells pooled from Ade- medium and transformants were further monitored for [URE3] propagation as described above for Cpr6. As seen before, cells expressing Cpr7 from the constitutive TEF promoter showed stable [URE3] on ½YPD (Fig 5). As expected, cells that lost the Cpr7-encoding plasmid (no growth on histidine deficient medium) show red colony color and no growth on Ade- medium. As we saw for Cpr7, we found that cells that express Cns1 are white and grow normally on plates lacking adenine, suggesting that Cns1 functionally complements Cpr7 with regard to [URE3] propagation.

Bottom Line: We show that Cpr7 interacts with Ure2 and enhances its fibrillation.The requirement of Cpr7 is specific for [URE3] as its deletion does not antagonize both strong and weak variant of another yeast prion [PSI+], suggesting a distinct role of the Hsp90 co-chaperone with different yeast prions.Our data show that, similar to the Hsp70 family, the Hsp90 chaperones also influence yeast prion maintenance, and that immunophilins could regulate protein multimerization independently of their activity as peptidyl-prolyl isomerases.

View Article: PubMed Central - PubMed

Affiliation: Council of Scientific and Industrial Research-Institute of Microbial Technology, Chandigarh, India.

ABSTRACT
The role of Hsp70 chaperones in yeast prion propagation is well established. Highly conserved Hsp90 chaperones participate in a number of cellular processes, such as client protein maturation, protein degradation, cellular signalling and apoptosis, but little is known about their role in propagation of infectious prion like aggregates. Here, we examine the influence of Hsp90 in the maintenance of yeast prion [URE3] which is a prion form of native protein Ure2, and reveal a previously unknown role of Hsp90 as an important regulator of [URE3] stability. We show that the C-terminal MEEVD pentapeptide motif, but not the client maturation activity of Hsp90, is essential for [URE3] prion stability. In testing deletions of various Hsp90 co-chaperones known to bind this motif, we find the immunophilin homolog Cpr7 is essential for [URE3] propagation. We show that Cpr7 interacts with Ure2 and enhances its fibrillation. The requirement of Cpr7 is specific for [URE3] as its deletion does not antagonize both strong and weak variant of another yeast prion [PSI+], suggesting a distinct role of the Hsp90 co-chaperone with different yeast prions. Our data show that, similar to the Hsp70 family, the Hsp90 chaperones also influence yeast prion maintenance, and that immunophilins could regulate protein multimerization independently of their activity as peptidyl-prolyl isomerases.

No MeSH data available.


Related in: MedlinePlus