Is Hsp70 a folder or a helper protein?

Year 2010, Volume: 1 Issue: 2, 18 - 24, 05.04.2013

Lütfi Tutar

https://doi.org/10.12808/bcs.v1i2.5

Abstract

Abstract

Abstract

Proteins are important macromolecules for cellular activity; intact and correctly folded proteins are required for normal cellular functions. Therefore, a cell has a unique machinery, using heat shock proteins (Hsp), to fold other proteins in their correct three dimensional forms. Several stress factors may cause partial or total destruction of native protein structures. This destruction can be reversible for some of the proteins. Heat shock proteins help some of the unfolded proteins to refold their native states and direct irreversibly denatured proteins to lysosomes for degradation. Hsp70 is at the center of this unique mechanism. Hsp70s also harbor other biochemical functions such as ATPase activity. This article discussed some of the functions of yeast Hsp70.

Keywords: Heat shock proteins, cellular function

Özet

Hsp70 katlayıcı mı yoksa modulatör protein mi?

Proteinler hücresel aktivite için önemli makromoleküllerdir, normal hücresel fonksiyonlar için bozulmamış ve doğru katlanmış proteinler gerekir. Dolayısı ile bir hücre proteinlerini doğru üç boyutlu halde tutabilmek için, ısı şok proteinlerini kullanan oldukça özgün bir mekanizmaya sahiptir. Birçok stres faktörü protein yapılarını kısmen veya tamamen bozabilir. Bu bozuklukların bazıları giderilebilirken bazılarını onarmak mümkün olmaz. Isı şok proteinleri bir yandan katlanmamış proteinlerin doğal yapılarını kazanmalarına yardım ederken bir yandan da denatüre proteinleri parçalanmaları için lizozoma yönlendirir. Hsp70'ler aynı zamanda ATPaz gibi aktivitelere de sahiptirler. Bu yazıda maya Hsp70'in bazı fonksiyonları tartışıldı.

Anahtar sözcükler: Isı şok proteinleri, hücresel işlev

Keywords

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