The Yeast Multifunctional Protein Hal3: Still a Source of Surprises
نویسندگان
چکیده
Protein aggregation underlies multiple of human disorders. Little is known about howglobular proteins aggregate into toxic assemblies under physiological conditions. Invitro studies have shown that generally polypeptides might be partially or totallyunstructured to aggregate, but recent studies have revealed that “native-like”conformations are able to self-assemble without need to unfold [1]. Here, we have usedthe FF domain of the URN1 protein to study the structural properties of the amyloid-like aggregates, as well as conformational and stability studies of the initial species thatpromote aggregation
منابع مشابه
Moonlighting proteins Hal3 and Vhs3 form a heteromeric PPCDC with Ykl088w in yeast CoA biosynthesis.
Unlike most other organisms, the essential five-step coenzyme A biosynthetic pathway has not been fully resolved in yeast. Specifically, the genes encoding the phosphopantothenoylcysteine decarboxylase (PPCDC) activity still remain unidentified. Sequence homology analyses suggest three candidates-Ykl088w, Hal3 and Vhs3-as putative PPCDC enzymes in Saccharomyces cerevisiae. Notably, Hal3 and Vhs...
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The Saccharomyces cerevisiae Hal3 protein is a moonlighting protein, able to function both as an inhibitory subunit of the Ppz1 protein phosphatase and as a constituent protomer of an unprecedented heterotrimeric PPCDC (phosphopantothenoylcysteine decarboxylase), the third enzyme of the CoA biosynthetic pathway. In the present study we initiated the dissection of the structural elements require...
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Saccharomyces cerevisiae Hal3 and Vhs3 are moonlighting proteins, acting both as inhibitors of the serine/threonine protein phosphatase Ppz1 and as subunits (together with Cab3) of the unique heterotrimeric phosphopantothenoylcysteine decarboxylase (PPCDC) enzyme of Hemiascomycetous yeast. Both these roles are essential: PPCDC catalyses the third step of coenzyme A biosynthesis, while Ppz1 inhi...
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The Hal3 protein of Saccharomyces cerevisiae inhibits the activity of PPZ1 type-1 protein phosphatases and functions as a regulator of salt tolerance and cell cycle control. In plants, two HAL3 homologue genes in Arabidopsis thaliana, AtHAL3a and AtHAl3b, have been isolated and the function of AtHAL3a has been investigated through the use of transgenic plants. Expressions of both AtHAL3 genes a...
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